Chad Ford has his Rookie Report out and he has some good things to say about our Rookies. He divides the Rookies into groups: The Good, The Solid, The Bad, The Ugly, and The Sleepers.
Rondo is included in The Good category and here is what he had to say:

Rajon Rondo, PG, Celtics
I had Rondo ranked at the top point guard in the draft almost all year and thought he should be a top 10 pick. He became the steal of the draft when he fell into the Celtics' lap at No. 21 (via trade from Phoenix).

So far in the preseason, Rondo has played as well as, if not better than, Boston starting point guard Sebastian Telfair. Only time will tell whether Rondo will be able to beat out Telfair for the starting job, but the facts are in his favor: Rondo is a much better defender and rebounder, and he has played virtually mistake-free basketball so far.

If he can learn to consistently knock down the mid-range jumper, he's got a chance to be a star.

Leon Powe, F, Celtics
It's doubtful that Powe will see much run on a stacked Celtics squad this year (in fact there's no guarantee he makes the team), but the C's have to be happy about his early play. The last few games he's been a force on the boards and in the paint. Powe has first-round talent. If the knee holds up, he could be a player down the road.