Not quite for free: Brandan Wright's a solid complimentary player, and there are picks. But, asset-wise, it isn't much of a risk for Dallas—chemistry's another matter, though.
Regardless, it'll be great for Rondo, in terms of his next contract. He may average fifteen assists over the remainder of the season.
Wright is certainly ok, but easily replaceable. I don't put much value in late first round picks in the NBA