What a great start you guys are making! Even in alpha, the file management speeds are impressive -- and I'm working with a 2TB library. Playback is very nice, and bitrates are changed to match the files. I have created a special view for classical music (that's my bailiwick) that is suiting my tastes quite nicely.
Of course I'm finding some bugs. Here are the most consistent ones. OS 10.8.2, Mac Pro with 8 cores. Music library on a separate internal 3TB drive. MC plays out via USB to a V-Link/192, thence to DAC and amp.
1) Tagging: the program can't really do this without crashing. I have found that sometimes if I tag multiple files it manages to write tags to some of them, but so far tagging is pretty much a guaranteed crash.
2) Clicks: after a while the program becomes generally unresponsive to mouse clicks. I have found that in most cases right-clicking (instead of left) gets it to respond again, but from that point until restarting the program clicks become hit-and-miss.
3) Resizing the main window from the bottom: sometimes causes a weird hiccup in which the whole thing just disappears, but the program is still running.
4) The occasional file plays with a bunch of skips and stutters. But stopping, then restarting playback, solves it.
5) Search: another guaranteed crash.
I'm looking forward to watching MC grow!