I'm using Windows XP. I have software that will do the organizing, but it doesn't necessarily get all of the information correct and sometimes I don't realize there is a problem until I try to use the file with a particular player or software.
I have ripped a lot of music and have everything nicely in artist/album/track order, but I didn't bother worrying about whether genres were consistent, date of album (what do you do for compilations and reissues?), multi-album sets (of which I have quite a few) which show up as different albums in cover-flow on iTunes if not tagged consistently, and now ratings of songs. A lot of this information may not be very important, but to get things clean and to be able to use Smart Playlists to its best advantage (which is extremely helpful for a portable that can't hold an entire music collection), it's needed and can be quite time consuming.