BioWare recently asked their community to guess how many voice actors they recruited for Dragon Age: Origins, and today the official number has been revealed. The average of all submitted guesses was 77, but the actual number is apparently 144. Even if these people only had 10 minutes of talking to do, that's a lot of dialogue.
As long as they didn't hire the three guys who voiced all the characters in Oblivion, I'll be happy.