She just made the announcement via her Twitter account:
It’s official: I’m hosting the
#Oscars! I’d like to thank @TheAcademy, my wife Portia and, oh dear, there goes the orchestra
I’m psyched about this! Ellen is one of the funniest women in the biz, and anything will be better than James Franco am I rite? I’m already looking forward to the telecast and it’s not even until next year.