Just read an AWESOME apparent spoiler, from a twitter user who apparently has had things right before, but has now has his account shut down.
Apparently, 8 returning players compete for HoH - 4 duos, but two players get evicted on the spot without entering - from different pairs.
So basically now, there are 8 newbies, two duos, and then 2 returning players with no official tie to any of the others.
Is this true? Who knows, but I'd love to see Dick/Danielle Jeff/Jordan and Brendan/Rachel competing individually.