Now it's a year later and I've used Windows 7 with pleasure for my daily work. It's still a great, but installing and uninstalled several applications, receiving numerous updates does have an effect on the product. Boot times are going up, Shutdown regularly starts to fail, Wifi now sometimes has troubles connecting and it starts to feel a bit sluggish.
Some of the more geeky people will now recommend to do a clean install, but I really hate doing those. Even when keeping most of my stuff in the cloud it's still to cumbersome. I still need to install alternative browsers, IM apps, Bookmark syncs, Adobe readers and many other things I always forget.
However I do need some medicine to boost performance, boot times and give my PC a good tune up. Microsoft bring on Service Pack 1 for Windows 7.
... alternatively I could have listened to my mom and use an Apple to fight my illness...