Yes, there should be another GP in North America. No, F1 cars don't belong on ovals. CART used to be where GP drivers went when they lost their rides.
It's probably just local rumor. The City of Long Beach is a customer of mine, and that's where I heard it. If Bernie is talking about it at all, it's probably just as leverage for another venue, in my opinion. But, damn, it would be nice.
As Dave said, F1 runs on money. And since F1 left Long Beach in the early eighties, CART and now Champ Car has turned the whole weekend into a giant piggy bank. There are three days of packed streets. Concerts, a street fair, Trans-Am, drifting, celebrity racing and more. Just a big party. I think the city and the promoter could match the money and crowds that Indy pulls without a problem. The infrastructure is already in place. Also, Toyota has sponsored the race for thirty years. So team it with A1 and it could easily make financial sense.
Anyway, a good F1 race 35 minutes from my house wouldn't be a bad thing.