Heh. And there's me on the Beat Hazard forums asking for FLAC support. 
yes flac is a must have
is the game worth getting
For the game itself, I would say yes.
But, it lacks some basic features, FLAC support was a big one, I've not tried OGG but I wouldn't be surprised if that's missing as well. However they use BASS (same as Audiosurf) so these should be easy to remedy once they recover from the inevitable torrent of audiophiles/geeks/sad gits like myself.

No unicode support yet either, which again is being asked for by many.
The Steam achievements are a bit lacking. There's no limit to the multiplier, so a 30 minute song on easy can see you get most of them as soon as you understand the basics of the game.
No resolution support and the game forces vsync off (even if you force it on through something like the nvidia control panel, the game will actively force it off during play).
Windowed mode is only achievable through alt-enter after the game is run and the window isn't resizeable, unfortunately.
So yes, despite that torrent of issues, it's because it's a cheap port from the 360 and has only been out on Steam for a few days. I'm sure most of those will be fixed but the game itself is fun.
It's less cerebral than Audiosurf (no puzzle element, just shooting with bullets / enemy spawn in time to the music) and I've not found any global high score tables yet, although they use Steam to compare your scores against your friends.