Ok, heres the run down. WMA files are perfect if you plan on using them for let's say, saving space on your harddrive or want to put a massive amount of songs on an MP3. WMA's audio encoder is very different to MP3 and it's compression ratio is better almost at no cost of quality, think how MP3Pro is a 64KBPs MP3, but with special software that you can download, that 64KBPs MP3 can sound like a 192KBPs MP3 (Which is the theoritcal KBPs for CD-Quality Music). WMA uses a simply compression system that is very different yet very similar to OGM (OGG's parent for sound files, OGG is the true original meaning for both Video and Audio codecs) a 320KBPs MP3 in OGG could be just about 500KBPs OGM (Which will be much bigger then an MP3, but perfect for LOSSLESS to LOSSY conversion). With WMA, you can take the same MP3 and convert it to a lower bitrate(44khz/320KBPs MP3 to 44khz/192KBPs WMA) to WMA without that much noticeable quality loss. Overall: WMA perfect for saving space with the kicks of MP3. But if you want perfect sound, Lossless all the way.