Here's an excerpt:
"In just two weeks, Xbox 360 will extend its industry lead with the year's most anticipated game launch, GTA IV. Launching April 29, GTA IV will be coming to Xbox 360 on day one. GTA IV will feature the first ever online multiplayer for the franchise and Xbox 360 is also the only place you can earn GTA IV Achievements and increase your gamerscore.
Starting this fall, only Xbox 360 owners will have access to exclusive GTA IV episodic content. Whether it's the results of online polls or data from pre-sells, consumers have made it clear that the benefits of Xbox LIVE and exclusive access to GTA IV episodic content are making Xbox 360 the chosen place to play GTA IV."
For the full Microsoft March NPD statement, check out Kotaku.