XBox versions of Crysis 2 will run better because of the high optimized code. Plain and simple. Also, Crysis for Xbox and PS3 have dumb down graphics. They don't and will never give you the full blown graphics experience the PC version does.
There are tons of videos on Youtube demonstrating what I just said.
Have you actually played the Xbox version? Theres very few differences. Take out the extra few shadows on the PC version and the ability to run at 1080p native versus 1152x720 and 1024x720 (PS3, both resolutions according to digital foundry), and theres overall very little difference. The PC version's only real advantages come in the form of being able to apply higher levels of anti-aliasing or other types of filtering, like anisotropic filtering.
PC verisons of Crysis choke computers because although parts are faster in raw performance, the PC port is unoptimized (even under nVidia's bribery) and has everything Crytek threw in graphics. Hence its expected to see midrange GPUs choke.
nvidia's bribery?
I actually think Crysis 2 looks better on the "High" settings versus "Extreme" because it turns off all of the stupid blurring effects.
I for one, still don't have problems with my HD 5850s. But I know they are being greatly tasked (heat output is high and fans are always at high revs). However, I can easily play at 1920x1200 resolution with extreme settings with every extreme graphics boost. Something the XBox nor PS3 will ever do.
As can I on my GeForce GTX 460 1GB at 1920x1080. But I wouldn't brag too much about it "tasking" your system, because it is a very unoptimized port. It's very dependent on post processing effects to make it look good.
PS - Size of the game folder (in GBs) means nothing.

Yes it does, in fact. Goes to show that no significant change was made to the texture set for the PC version. If you want an example of a PC game that was upgraded in the process of being ported from consoles, look at Grand Theft Auto 4. That game is twice the size of the Xbox 360 and PS3 versions. The in-game textures are significantly higher resolution than those found in the console games, especially when compared to the already lower resolution PS3 version. Even Bad Company 2 has a few extra gigs on the Xbox 360 version.
Just because your notebook or desktop hardware is so much superior to the console does not mean that you will have a superior gaming experience on your ten to twenty times more expensive rig. And to add insult to injury, many blockbuster games are not even ported to the PC/Mac anymore, or if they are ported, it happens with a delay of several months.
Ten to twenty times more expensive than the consoles? You don't need to spend $2,000-$4,000 on a PC to get a better experience than the consoles. $600-$700 on a PC will get you a system that is capable of running all modern games, including Crysis 2, at 1080p native with details set to highest, with 4x MSAA and other settings not usually available to the console versions at lower resolutions. That will have a GeForce GTX 460 1GB or better GPU, 4-6 core CPU, 4-8GB of RAM depending on where you shop, etc.
Only a few games these days have long delays. And usually it is an upgrade. Look at GTA4. Significantly upgraded graphics compared to the Xbox version.
Only a few games don't get ported, and those are generally the console exclusives. Like Halo 3, or Uncharted. I couldn't care less about the PS3 exclusives. But the $199 Xbox 360 is good enough to keep around for Xbox exclusives, like Halo, Gears of War, Forza. There are quite a few PC games that will never make it to console, like Starcraft 2. Or when certain PC specific games are ported, they're basically terrible watered down versions, like every single non-PC version of every Sims game.
And again: Games are ported TO the PC. The times when they were ported FROM the PC are over.
Thats not true. EA has confirmed that Battlefield 3's lead platform is the PC. And they've gone on record as saying that, since the current consoles are so old, more games will have the PC as the lead platform.
So what real advantages do you expect from a ported version of a console game on your high-end hardware? That playing it with a keyboard and mouse is more efficient or feels better? That you have a chance of stress-testing the cooling fans of your Mac and finally find out how loud that machine can be? Or that you can play it at the full native resolution of the 27" display with all effects turned on only to find out that the game does not even take advantage of that anymore because it was optimized for much weaker hardware and thus does not even look that much better on your desktop machine than it does on the console?
That's not always the case at all. Look at Battlefield Bad Company 2 and DiRT 2. Both were console ports. However, they did have DirectX 11 features added in. Subtle effects that basically added more natural shading. But combined with the fact that they did actually include higher resolution textures, at 1080p native, those games compared to the console versions are absolutely gorgeous. And they run significantly better. Look at DiRT 2. On the PS3 it runs at 1280x720 with QAA. The Xbox 360 version runs at the same resolution but with 4xAA. The PS3 version struggles to maintain 30 frames per second. On the PC you can run it at any resolution you want, turn on the DX11 features, turn post processing and other features up higher, including setting anti-aliasing higher, all while maintaing a higher steady frame-rate. On my GTX 460 1GB I can set everything to the highest setting and run 4xMSAA and maintain a solid 60fps regardless of environment and with all cars on screen. A friend of mine is the only person I know with a PS3, doesn't own an Xbox 360. He recently bought a new notebook with a GeForce GTX 460m in it. Always emailing me about how amazed he is at how much better the PC versions of the same game look.
Even a game like Modern Warfare 2 or Black Ops, where every asset is the same on the Xbox 360 as PC (in MW2 for PS3, certain lighting effects are missing and it has severe frame-rate issues, also Black Ops runs at a significantly lower resolution compared to the Xbox 360 version), theres a big difference. You can set resolution up as high as you like, add in as much anti-aliasing as you like, set anisotropic filtering so high that textures miles off are still full quality.
So even in games where there is no change in assets, such as the PC and console versions having the same textures, just being able to set the resolution way higher is a big plus. Especially if you're coming from a PS3, where more games than not run at sub-720p and have horrible screen blurring and even worse frame-rate issues.
Spending money on high-end gaming equipment just isn't worth it anymore. You'll still have all the drivers and copy-protection issues that we've had ten years ago, it'll still cost you an arm and leg to keep your hardware up to date but you'll get only little - if anything at all - in return.
What driver issues? I've NEVER had issues with nvidia drivers and I've always bought hardware from reputable vendors, so none of my add-in cards or motherboards have ever given me driver issues either. In fact, nvidia GPU drivers can uninstall old drivers and clean install new drivers without a system reboot these days.
Copy protection can suck. But thats when you speak with your wallet and don't buy games with bad protection. Most non-Steam EA games aren't bad. I bought retail copies at Best Buy of Bad Company 2 and Crysis 2. Both use SecuROM online authentication. Activation and De-Activation are done automatically.
Here's the ideal equipment for those purposes: A 27" iMac on OS X with a Belkin adapter and the Xbox 360 connected to the Belkin adapter via HDMI. Great computer, great display AND a great gaming rig that can run all of the latest titles perfectly - because they were made for it.
Not really. Best to let the Xbox 360 do scaling for displays. The Xbox 360's scaling hardware is definitely the best of the current consoles and it does a pretty good job at scaling 720p games up to 1080p and making them look NEAR native 1080p quality.
For the price, the 27" iMac has both a weak CPU and GPU and only about 1/4 of the RAM as it should at that price.. You can get FAR better for significantly less if you build a Windows PC. Plus games run way better in Windows than on OS X. For a few hundred dollars, you can build a Windows PC with a GPU that smokes the Radeon 5750 in the iMac, like a now cheap GeForce GTX 460 1GB (around $180, $130 with rebates) or an even faster, but still relatively cheap, GTX 560 1GB (around $230). You can get either one of the AMD Phenom II X6 CPUs or Core i5 or Core i7 (if you want to spend a little extra), 8GB of RAM, blu-ray reader, all of the necessities. You'd also be able to throw in a nice MATTE (no glossy!) LCD with an IPS panel and true RGBLED backlighting versus Apple's edge-lit LED backlights. Even after all of that you would have only spent about half as much as the iMac. And two years from now the only upgrade you'll need is a faster GPU. And, unlike the iMac, you'll actually be able to upgrade it.