According to Michael Ausiello of EW.com, GLEE has been renewed!
FROM EW Website: This just in: Fox is on the verge of announcing a full-season pickup for Glee, sources confirm. The show, which has performed solidly in the ratings, initially received a 13-episode order from the network. The back-nine pickup brings the total number of first-season episodes to — I suck at math but I think I’ve got this - 22.
So, this means a full season instead of the half-season as first promised.