I loved XP using the XP lookalike Theme...
I never liked and never will like the grotesque and completely cluddered look of Vista. And I absolutely can't understand why anyone would want to make their XP look like awful Vista. The glossy look kills all overview, let alone the widespread use of transparency. No. Just give me my good old fashioned single-colored UI elements and I'm happy. Though I have to admit Win7 does things right: It does implement transparency and "glossiness", but not so exaggerated like Vista. It doesn't destroy overview and adds a nice fanciness.
Reason for switching to Win7 were simple. I planned to do that nevertheless in 2-3 weeks and just yesterday my XP broke down once more and I decided to shoot it to hell and typed format c:
And Win7 is just awesome. Of course you have to adapt to it at first (as it handles many things different than XP, actually the file handling is almost the same as Vista) and there is some more stuff to configure, but some hours and you are "in". Of course, I had to retrochange some stuff (e.g. I need a proper oldfashioned task bar and hate "grouped" symbols down there. And I need a quick-launch bar. Luckily, it's easy to change the appearance of Win7 easily to your personal preference. And of course you still have to change all the things you had to change back then in XP too...invisible folders, stupid "minitile" view instead of a proper detail list etc. But that's minor stuff.
Here a screenshot of my still unfinished working place. There are a lot of shortcuts missing (especially the quicklaunch bar soon will be cluttered again...I place all program shortcuts there, game shortcuts and "generic" files go to desktop). Desktop itself is also cluttered, as I just imported that from my "old" XP. Some dead links, some missing stuff, some wrong-placed stuff...the usual.