It does pose a bit of a challenge when testing, though. Alt-tabbing between the desktop (or Firefox or Textpad) and WW causes my system to chug. And I'm sportin' some pretty good hardware -- Athlon64 3500+, 1GB ram, 256mb Radeon x700 -- so it's challenging.
Not that I expect you to fix it just for little old me, and I'll continue playing and testing, but I did want to chime in.