I don't think "refused" is the right angle for the situation. Here is the origin of that statement.
1UP: Why didn't you show Grand Theft Auto IV at your press conference? Why was it not there?
Tretton: Well, Dave [Karraker, Senior Director of Corporate Communications at Sony Computer Entertainment America], do you want to answer that? Dave was in control of the content.
Karraker: You want the real answer?
1UP: Can you give me both answers?
Tretton: [laughs]
Karraker: I'll give you the real answer. They didn't send us their video.
1UP: So it's not anything like "well, the game's been shown on Xbox 360..."
Karraker: We requested it. We sent an e--mail out to every publisher and said send us your videos that you want put in the press conference, and they never sent it. Not much more you can say about that.
1UP: Can you guys say if you're going after any exclusive content ala Microsoft's two episodic entries?
Tretton: We have some pretty good information in terms of what our plans are with Take-Two relative to GTA4, but I really want to make sure we get you all the exact facts, so we can get you something from Dave pretty shortly. [Phil Harrison dodged a similar question from 1UP last week, as well. "...we're actually working closely with them [Rockstar] on a number of initiatives, so I do know some things that are going on, but I'm not able to share those with you now," he said. -- Ed]
http://www.1up.com/do/newsStory?cId=3161348