Ladies: Kwan, Cohen, and whomever, as everyone else has said. I think either Kimmie or Jane will do it. (I love Mok, but she isn't healthy yet)
Men: Weir, Goebel, Jahnke. This is contingent on Johnny and Tim getting over their current afflictions.
Pairs: I&B - since they made the GPF, I think they are a lock for top 2. Their throws, which were so inconsistent last year, were all landed for positive GOE so far in GP, too. They are trying the 3lutzes in both the short and long and will probably mess them up. However, they are doing a 2A2T combination rather than a 3t sequence, and they do it very nicely. It's been scoring well in their GP. Their SBS spins are top notch now. Could finish as high as 7th this year at Worlds.
Don and Hunt have had really great SP's, but have completely fallen apart in the LP's. Also, although you are allowed 14 elements in the LP, they are only doing 13 (essentially, the junior program) and quite easy lifts. They have run out of steam at the end.
O&L have been struggling, but have been better in the GP in some ways that D&H, particularly in the LP. Since Nationals is using 6.0, and under 6.0, he who finishes ahead in the LP wins, my prediction is for O&L to be behind D&H in the short, but finish ahead of them in the long. Vise and Kole are way weaker than all of the 3 top pairs from last year.
Dance: It is mathematically possible for the US to get 3 teams for Olympics next year. G&P have been doing quite well in the GP! They have beaten several teams that were ahead of them in Dortmund (Faiella/Scali for example!). I believe G&P finished 4th in both their events.
If B&A make the bronze medal at Worlds, and G&P get 10th place, that would do the trick, and is very possible. I expect Matthews/Zavozin to win the bronze medal at Nationals. They just won the Jr. Grand Prix Final, so that should make TPTB look favorably upon them. I would like to see them add some difficulty to their LP though.