The sound stutters on my XP laptop, but someone said that's a magicsound call that's not working right (or something like that, I'm no techie) on the apple forums...
On the OS X side of things, it works great, but if I close it and reopen it, the window defaults to a minimum height that, with the dock on the bottom, and my screen res. set to 600 by 800, makes it too big and I have to drag the window over so the corner's not covered by the dock and resize it.
Oh well, overall I'm happy with it. Sure Apple better fix this crap soon, but I wouldn't not download it.