Could just be him playing to the crowd. He is debuting Fast Five in Moscow as it is in the video.

I haven't seen 5 yet, but from the Wiki page it sounds like they set it up for another sequel. It's pretty surprising as it is though, considering Vin Diesel doesn't like to do sequel movies back to back. Maybe he's realized that the only type of movies that actually do well for him are action movies for established franchises.

Another one? What will they call it? Fast and Furious: SPEEDIN SIX? Lolololoz