I like Windows 7 a lot. Upgraded from XP about three weeks ago. I used the 64 bit upgrade and saw an instant increase in speed in my AMD Athlon 64. Now I can use all the power it has. Even my DSL is quite a bit faster. The only thing is DRIVERS for older stuff. I can't seem to find any for my Epson scanner so I still have it hooked up to my back-up machine with XP. W7 doesn't want to give me full access to my external hard drive either, says I have to have "permision" to move any thing on or off it. I had to upgrade my Outlook from 2000 to 2007 but I really like 07 so not complaining.
Yes but understand most of the power and speed you've gained through upgrading was going to 64bit processing...
Mind you, 64bit XP was a joke, it was incredibly unstable and has basically no support.
So, if you really want 64bit processing power and you have a 64bit processor, yes, it is a good idea to go Windows 7; but make sure you do a complete reinstall and not an upgrade, because upgrading to 64bit from x86 (32bit) doesn't work!