When do you think obama will announce his vp?

believe it or not I will be voting for him or against him, depending on who is vp is. I am one of the few undecided voters left. After I hear who is vp will be I will either be voting obama or barr. My worry is that he will pick someone like hilary or biden, both who I consider socialists! I am hoping it will be either richarson, edwards, or kerry!