Almost as soon as I'd installed Win 7 RC in a vmware, and saw that it was good, I reckoned it was time to give it a go as my main OS. The main reason I have for upgrading is for performance and it was obvious that running it virtually wasn't going to be fun!
So I used gparted to resize my main partition. Luckily I had over 100GB free so I was able to create a primary partition of 50GB for Windows 7. I booted off the install DVD and installed windows as you normally would, and now I have the option of booting into my earlier version of windows (XP) or 7. After installing most of the stuff I need day-to-day I've used about 10GB of disk space.
I've had to do some testing and application support on Vista, but I haven't used it for any length of time, so everything in 7 is new to me. So if I say "hey, Windows 7 has this cool new x" don't come back to me saying "Duh, that's not new, x was in Vista". ;)
Having said that, I think having to use Vista broke me in gently to some of the new concepts and made me more accepting than if they were brand new. For example, I don't know why my programs menu has to be limited to a tenth of the screen space. I much preferred the ever expanding sea of grey that you got on an old XP system. But I'm getting used to the new start menu, and I daresay I'll start using the program search in time.
There's lots more to come on Windows 7, but from first impressions it's looking good. It's fast and responsive, and I haven't hit any brick walls yet during my usual work, although some things take a bit of Googling to see where/why things have moved! Hopefully I'll get a chance over the next while to do a few little posts. One thing I'll definitely do is a list of compatible programs & applications. So far only two haven't worked and they were both games!