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I have used Windows 7 since the Release Candidate originally came out (I upgraded to the final RTM when it was available for download via the MSDNAA program at my university), and I pretty much agree that it is worth the upgrade.
But honestly, listening to all of this Vista bashing is getting kind of repetitive, and for the most part, the "complaints" about Vista aren't very valid since most of the actual issues were fixed with the release of SP1. I mean really, negative perception is so prevalent that people will refuse to buy a new computer unless it has XP on it. If you didn't know, sources show that 61% of all personal computers in use today are still running XP. I mean, I was an XP user for many years before I ended up buying my new Thinkpad (which now uses Windows 7), but I think it's about time for people to move on if they have the capability to do so. http://www.smogon.com/forums/editpost.php?do=editpost&p=2288019
I will say that not being able to upgrade directly to Windows 7 from XP could be discouraging, but I think clean installs always work out better in the long run.