Sean Obi is a transfer, one of only four I think that K has ever taken (Curry, Jones, McCleod I think are the other three?) 6'9, 270 sophomore center. Averaged 12 and 9 in C-USA (led the conference in rebounds, the second highest freshman in the country in rebounding) and led Rice in scoring. Had a really good shooting percentage as well. Big guy, big wingspan, definitely a below-the-rim player. Will get some time at C, but not sure if he is ready to step into major major minutes.
The PF and C position will actually feature a LOT of size and some decent talent/experience... Plumlee has really come on (remember, he has two seven foot brothers who weren't very good their first few years but eventually matured into NBA players... and Marshall showed a lot of growth by the end of last year) and Amile Jefferson is a very underrated guy with a GREAT feel around the basket and who can play some good, long-armed defense. Jeter is ranked around 10 overall. Very long, very bouncy, great rebounder and shot blocker who can dunk up close... huge wingspan. Not a OAD threat because his offense isn't great, but could get to the league in year two, after a bit of development. No stars in the PF/C role, but a lot of really good, beefy, strong, long, D-minded bodies with some skill.
Duke will be good, but very young, unproven, and without the talent of the freshmen trio from this year. Likely not winning any titles or anything, but should be pretty solid. Ingram, Thornton, Allen, Jones, and Kennard can all score. Should be a lot of guard and SF scoring, with the big boys providing a lot of muscle inside. Defensively should be a real brute of a team, although the offense won't necessarily be (although with Thorntons ability to pass inside and off the dribble and the bigs ability to flush it, you might see more buckets from the PF/C spot than you might at first expect.)
Definitely a top 10ish team all year, with the ability go go higher, given how weak the year looks overall.