Over Twitter, Chris Cornell announced Soundgarden would reunite:
The 12 year break is over & school is back in session. Knights of the Soundtable ride again!

Full scoop from Spin:

Rumors of the reunion have run rampant over the past year — and for good reason. Last March, guitarist Kim Thayil, bassist Ben Shepherd, and drummer Matt Cameron (who is also Pearl Jam’s full-time sticksman) played three Soundgarden songs — “Nothing to Say,” “Spoonman,” …