Just without him pretending to be a really old man who can barely walk. He also sides with Cersei a tad more subtly than his "Treason is...Treason!" speech in the show, but in general he is very similar. I just didn't care for them making him a fairly spry old man pretending to be a rambling old fool, when in truth the latter is exactly what he is.

And in answer to your second question below, my main complaint about Robb is how he treated the Lannister spy they intercepted, and now in this episode where he was angrily hacking away at a tree to show his despair. The Robb in the book was much more in control of himself and kingly. Though I feel like the Robb plotline has really suffered in the show, and the absence of many of the necessary characters there is really showing. Add to that the mere 2000 men he supposedly sent to attack Tywin, and whatever issues I have with how Robb is portrayed are eclipsed by these much greater issues.