Phil was on TES this morning. Nothing really new given away, but it showed the teams running from the Santa Monica Pier and three contestants falling down (Donny, Jim twice, and another guy, although it might be Donny again.) He explained a little about the yield, and basically said it could come back to haunt a team that uses it, which I'm guessing means that teams will know who yielded them. He said this is the best cast they've ever had, saying that every other season was good and some teams that were okay, but this year is going to be ultra competitive. He said Charla may be a little person, but has the heart of a whale, and we'll get to see how competitive she is in the first episode, and the Bowling Mom's will surprise a lot of people.
Also, this race travels 75,000 miles this time, and goes from hot to cold to hot to cold. Phil said the teams looked like prunes when they were done.
Here's two stories from TV Guide, one a review of the show that lists all the countries the show went to and the other is an interview with Phil.