Hey Dsync,
1.) My HDD doesn't make that much noise, no. A light hum, but nothing distracting or overbearing. That being said, occasionally I keep my cell phone on my desk, and I have thought a couple of times that my phone was vibrating when it was actually the iMac. Like I said though, nothing that would deter me from getting one. My room is small and so that's definitely something that I would notice.
2.) I'm mostly a casual user in terms of apps. I'm not running PS or anything frequently (although I do use it on occasion I haven't started it up yet). I'm usually running the basics (firefox, itunes, amsn, word, ical, steam) and so for that I am well aware that I don't need the capabilities of an i5. As mentioned, I've played Portal, Starcraft 2, and a couple of others with no problems on decently high settings. They look fantastic, although Portal clips a little bit when you move the mouse quickly from side to side. I may not be the best person to ask for how it would run CS5 production edition because I never have. It seems to me though that this computer would be quite capable running such things.
3.) The guy at the Apple store was a graphic designer who used an iMac C2D which he has had for 3 years or so and with that he has never really encountered any problems. Seeing as my use was geared mainly towards games, he said that the dif between i5 and i7 would be negligible because that's mostly the realm of the gfx card. He did say though that in terms of rendering graphics and editing hd video that the difference between i5 and i7 was like so: "If you were doing it on your i7 and it took 50 seconds, it may take something like 70 seconds on the i5." Now I'm also aware that if you blow that statistic up, it would translate to a decent chunk of time, but in terms of the ability to perform, he said that the i5 was more than capable of handling its own and would do what you needed it to do in slightly more time. I wasn't too keen on paying 220 more for the difference between 2.8 and 2.93, especially if I wasn't going to use it to its full potential. If you are, though, then you may want to go i7.
4.) I was actually going to buy on the refurb store but my decision not to was based on a couple of factors: I couldn't wait anymore - I needed to get rid of my macbook asap and so I couldn't afford to wait for the delivery and such. I also wanted to deal only with a store. I've read imacs have been having problems with screens (mine seems more than fine, btw) so I wanted to be able to go directly to a store without having to wait for them to ship something to me and me having to ship to them...too much of a pain imo. I would strongly suggest/recommend going to the refurb store though. I've heard in many cases they're better than new because they've been checked out and people I know who have used it have never had a problem. Go with what's more economical if you're on a budget. You won't regret it.
Hope this helps! Feel free to follow-up.
