Its been out for almost a week now.
I've been playing CSS for a few days now. Its really stable, but not bug free, but the bugs are annoying, not show-stopping. Performance is exellent, provided you get the video driver setup right.
It's been more then 10 years since i tried linux and played CS, now a decade long dream has come true. "THANKS GABE".
For all those interested in steam for linux, here's some tips:
1) start withh Ubuntu 12.04.1 64 bit (not ubuntu 12.10) and DON'T manually add the gpu drivers.
2) add the xorg-edgers ppa(google it) [ its a 3rd party repository for graphics drivers, they wil update both your kernel and gpu drivers automatically, without loosing stability.]
3) install Steam(linux). When you start steam, it will update itself. Once you start it, it will prompt you to install the latest proprietary drivers. NOW install it from this prompt.
My system : Phenom 2 965, 8 GB RAM, 6950 2GB.