From what I've seen Rondo has mostly been taking those jumpers when we have a nice lead and the shot clock is winding down. Personally I hope he takes 15 foot jumpers consistently to get his confidence up. If he could master the 15 footer then his game, and our team, would have a whole new dynamic that would be difficult to guard.
Some of his jumpers last night weren't good ones to take (i.e. 3pointers), but we had a 20pt lead so it was tough to get mad.
Glen Davis on the other hand has been taking jumpers outside of his range, when he should be playing more under the hoop. I thought towards the end of last year and into the playoffs Glen did a better job of using his body to draw fouls, etc. He seems to be far more productive cutting towards the hoop for 1-dribble "catch and go" plays. I'm not trying to discriminate against Davis for his jumpers and not Rondo, but I think they are different situations. Now, if Rondo stopped penetrating & dishing and instead was calling for the ball to take jumpers then I'd definitely have a problem with him.