Overall, happy with the device, and want one. I'm trying swing getting it "free" as I have (somewhat significant/milestone) birthday coming up and I also just (finally) graduated, so I've got a little card to play with a few family members.
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Either way, I think I will pick one up sooner or later; if not now then the next revision.
The major complaints, for me are:
(Hardware)
1. Pricing. The $130 surcharge for 3G option is a little steep. Also, $100 for 16gb more hardly makes sense with 32gb upgrade being just $100 again. I can see $100 for a 32gb bump, but the $100 for just 16gb is out of line. I would have liked to see the 16gb base model priced where it is, and then offered the 32gb with 3G for $100 more, and the 64gb with 3G for another $100. Not a deal breaker, but a little disappointed.
I'm also not one of the people shocked by the cost. $500 is about what I expected, and I was hoping for 32gb at that price, and was hoping to be shocked by a $399 16gb model.
2. The screen being 4:3 is weird. I'm actually confused my the display. It doesn't LOOK 4:3, and the device, including bezel is 5:4. The 3:2 ratio of the iPhone was pretty good for a handheld imo. Not a deal breaker, at all, but just a little confusing.
3. Camera. At first I didn't care about it, but for what this thing is, a tiny little front facing VGA cam (like the one in the nano) would be a pretty cool feature. It wouldn't have been very large or expensive (look at the nano) so it seems like a pretty obvious omission.
(Software)
4. Native printing - offering an office suite with no system wide printing is really dumb. I think we'll see network printing as a system wide setting very quickly. Not a huge deal, but just an obvious flaw in my opinion.
5. Multitasking. This is a pretty common/old complaint, but this thing should really have multitasking. I think this will be addressed quickly in the OS4.0 update, though. I am very curious how it will dealt with, but I have a suspicion it will not satisfy everyone. I wonder if we will see a "dashboard" application that will host applets which runs along side one "regular" app all the time. Most of the multitasking people want to see is stuff that an applet would satisfy. A twitter app, Pandora, email notifier, calculator, RSS readers, a control panel widget (I want to adjust brightness without quitting my app!), etc etc. I would be really pleased if they just let you run OSX widgets. That would satisfy me in terms of multitasking.
I think the software problems will be dealt with pretty quickly (I predict OS4.0 pretty shortly after the 3G model is released) and they will address some/all of these concerns.
None of the hardware problems are huge, for me, so all in all pretty satisfied, and do want!