The crossfading and volume leveling are still a little buggy. Sometimes it skips 3/4 of the song, while crossfading to another song.
Volumeleveling sometimes lowers the volume in the middle of a song and that is very irritating, I actually have to adjust my speakervolume again.
Also, it runs kinda slow, slower than WMPXP (=8) that is. Perhaps it's the new design with all the colors (cool when adjusting the color in real time).
In short: a nice start, but not completely bugfree, but hey, it's a beta AND a M$ product, so what did you expect (j/k).