Apparently Soundgarden "reunited" in Seattle without Chris Cornell at Tom Morello's The Nightwatchman show. Chris Cornell was too busy promoting his new album to attend (the album is terrible anyway, he wasted his time). Story here: http://www.mtv.com/news/articles/1607805/20090326/soundgarden.jhtml This guy has fairly decent videos of what they played: http://www.youtube.com/profile?user=mattwong26&view=videos&query=tad-garden
I know Cornell isn't quite the singer he was but that would have been a great performance with a better vocalist. Tad sounded awful, from what I can tell. The drumming is immense though.
Maybe Chris Cornell will realize he hasn't done anything close to listenable since Audioslave's S/T and will get back together with Soundgarden and make some good music again. It's not like he has anything better to do.