Though I was lazy to download Win7 RC due to exams and stuff, I got a copy thanks to the Microsoft .Net Forum Sri Lanka. I installed it on a separate partition since I didnt like to replace my 64bit Vista with this 32bit version. Here's a personalized review of Windows 7 mentioning the improvements in my interested areas.
(There are tons of in-depth Win7 reviews out there. This is just a personal preference of feature additions that I stumbled upon in my usage)
Overall, Windows 7 is snappier and cleaner to the highest level. Here are some additional things I noted:
Displays the really usable memory in system properties
See this post. 32bit OSes cannot use 4GB RAM. They are limited to 3.25GB. On my system, XP 32bit showed 3.25GB as full memory available. But in Win7 32bit it shows both the real memory and usable memory in system properties. This would avoid user confusion in situations like I faced as in the aforementioned post.
Performance Index Differences
Performance Index scale has been changed in Windows 7. Compare the rating I have in Vista and the new rating. In Win7, CPU and RAM performance index have been moved higher. I got a lower index for hard dist performance since I installed Win7 on an IDE hard disk. Otherwise my Base score in Win7 would have been 5.7, compared to 5.5 in Vista.
Detects iPhone even without iTunes driver
Windows 7 detected my iPhone straight away and allowed me to use it as a camera. In XP and Vista, the iPhone won't even charge from the USB without the driver installed. This would make my life a lot easier if everybody had Windows 7. :-) It's worth to mention that Ubuntu had this driver built-in from some time ago.
Video format support
The video formats we love; xvid, divx, h264 and more, are natively supported in Windows 7. So you can watch your films even without installing a codec pack or another player. But for subtitles, you will need a player like KMPlayer or VLC.
Sinhala Typing isn't fixed yet!
That wiered Sinhala typing problem we had in Vista, still exist in Windows 7 as well. I had to install Vista Sinhala Quick Fix to fix that.