I will give you my personal opinion after having the opportunity to test the S2 for a couple weeks. The app memory and wireless additions are nice. The keyboard is "stiffer" and more responsive which I think is a plus also,but I'm using the credit card trick under my battery door and to be honest can't tell allot of difference between the two with it in there. But then again you shouldn't have to use a "trick" to get it working better.
The software is buggy like the S1 on 5.0. I find it interesting that the S1 software is a higher version than the S2, makes me believe it was rushed to market? The S1 and S2 perform about the same as far as speed goes. Internet browser is the same and performs about the same on both units.
Battery life is about the same as long as you turn off the wireless when not using it. It takes a little more with it on but not a crasher either.
All in all it is a very good phone, but as one of the people who have not had any real problems with my S1 I don't think I would upgrade unless the price was right. I would pay say $50 or so to upgrade but not the current promotion and certainly not the retail of $539 off the website.
As Cromwell has stated and I agree, lay low for now. Wait for a better deal on it or some other future release.
Just my opinion hope this helped.
Is the Storm2 that much better than a Storm1?
Trying to determine if I should upgrade or not.
I would also wait, it's all over the web about the end and back keys not responding on the Storm 2, sounds like RIM has another Screen Problem on their hands. So I wouldn't trust the Hardware right now.