First, I'll answer the question that most everyone seems to be asking:
Q: Should I upgrade to Windows 7
A: If your XP or Vista is working for you, don't waste your time or money upgrading. (If it ain't broke don't fix it) If you plan on buying a new computer, certainly try Windows 7.
Q: Why did *I* upgrade to Windows 7?
A: Because my computer came with a free upgrade. (can't beat free... might as well try it)
My first impression is that I like it. There are some differences in how things are done but as I'm figuring out the new ways, I must admit that most of them are better than the old ways. Also, my laptop is noticeably faster! When I click something, something happens NOW as opposed to 10 seconds later like with Vista. I did some video tests and found my processor utilization is much lower, even when watching an HD movie in full screen mode. This is going to help all of those users who like netbooks. (like me)
One major difference I've noticed is that the User Account Control is far better than in Vista. No longer does my computer pop that annoying window every time I go to do any sort of administrative activity. It only pops-up when I'm about to do something that will have a MAJOR affect on the system. For those of you who don't like User Account Control at all... you have the option of "throttling" it up and down. You can set it to be totally paranoid or you can throttle it down so it hardly does anything. You can also turn it completely off if you want.
The upgrade did take some time, but that has to be expected when you give your computer a brain transplant.
I must admit that I intentionally did a few things to really challenge the upgrade process. For one thing, I left my system partition encrypted with TrueCrypt (a free, open source hard drive encryption system that will totally encrypt your entire hard drive... you cannot even turn on your computer without a password). I did a backup expecting the upgrade to totally screw up my system because of the encryption, but it didn't!
When the upgrade rebooted my system I got the dreaded "Missing Operating System" message. (this basically means you are SCREWED) I calmly inserted my TrueCrypt rescue disk which setup the critical encryption boot loader and my system booted just fine... however it booted to my old Vista instead of the new Windows 7. Again, I was quite impressed at how the upgrade was sophisticated enough to prevent a totally system meltdown. I used the TrueCrypt tool to decrypt my system and then rebooted again. This time the Windows 7 Upgrade process finished without incident.
Once the Windows 7 upgrade was finished I used TrueCrypt to re-encrypt my system.
Very cool.