Advantages:
Clean, simple small footprint, not a resource hog and basically ten times
better than the cr$p that Microsoft have made of WMP.  Not that I bother
either with recent versions of WinAmp, finding that v2.7 meets all my needs in
that area.  Personally I find that all versions of WMP since 6.4 aren't worth
the space they consume and the sooner Microsoft are forced to return to
providing basic operating systems and allowing users to install those
applications (media player, browser, mail client, instant messenger client,
etc.) they want the better for all concerned, not just those on the EU.  If
Microsoft want to compete in the media player market then that's fine by me
but don't force users to install the crudware.  Same goes for most of the
other applets and applications that are being forced on users regardless of
whether required or not.

Disadvantages:
None that I am aware of unlike those of WMP9 which could take a couple of
hours to list.