The newer Anthlon and Pentium processors were primarily designed with XP in mind, so I am assuming that when WMP9 came rolling around the corner, Microsoft had it in mind that the majority of users would be running XP with one of these faster chips. My two-cents- honestly, I have not the faintest clue why anyone would have any problems with the software. I have had none since I downloaded and installed it. I have had one or two instances with one or two particular media files not playing as I knew they should, however, they were older files or files that I am not so certain were of decent quality. Really nothing that could not be remedied by adjusting the player settings or searching for older codec softwares.

Personally of the WMP series thus far, I prefer "9" best. This version comes closest, IMO, to what I originally found appealing with Winamp. Quicktime is still needed for it's trademark file formats as well as Divx for a few odd .AVI types, but overall, I think that Microsoft made vast improvements since 7 & 8.