Quite an impressive feat, but to be fair, we've faced 4 teams so far with weak interior defense (yes, that includes the opening-night Heat) that have played off Rondo, giving him room to work.
Starting with the Bucks tomorrow, I expect things to become a lot harder for Rondo in terms of having the freedom to dish out all these dimes. We won't be facing the Cavs, Knicks, and Pistons every night.