wow, quite a heated discussion over my original post!!  i appreciate all points of view... honestly, at this point, i'm leaning to just leave Windows 7 on the machine, as, by now,  it already comes pre-installed in the laptop i want to buy (the version is Windows 7 Home Premium 64-Bit)...

I mean, it has to be easier dealing with W7 than looking for all the drivers the laptop will need for XP... so, i will just try it with my Poser 6... if i notice that is too unusable, then i'll have to format and go back to XP, but i am trusting that Microsoft took the hint and made W7 a little lighter than Vista... as a matter of fact, i read that Windows 7 can even be used on netbooks, something Vista cannot do, so, i'll give it a try.

Thanks to everyone once again for all the valuable info!