ICS is about 95% there. (TexasIce version) New releases every 2-3 weeks, on average.
I've been running it for a month. Issues:
1. "Sleep of Death". This is a bug that causes the phone to lock up while sleeping, requiring a battery pull to reboot. It is much less frequent with the latest build but still happens now and then. I'm averaging about once every 3 days on mine. They say flashing the Tiamat kernel fixes it. I haven't tried yet.
I say average, because it is completely irregular in frequency. I can get 2 in one day and none for the next 5, or one daily for several days. I'd hate to have to try to track this one down.
2. Camera video crashes. Stills okay. I don't use the video camera function so it's not an issue for me.
3. I had a problem with the headphone jack not detecting a plug-in and switching off the internal speaker, necessitating a reboot, but that seems to be a problem in PowerAmp. Disabling the daemon that watches the headphone jack for plug-ins in order to autostart playback seems to have resolved that.
...Sean.