I stumbled on this early this morning, and have already ordered four: the Houston Astros' 50th Anniversary Collector's Edition, which will be released on May 15. This guy reviewed it, and says that the five discs in the set include:
*Nolan Ryan's 5th no-hitter on 9/26/81
*Mike Scott's Division-clinching no-hitter on 9/25/86
*2005 NLDS G4 (the 18-inning Chris Burke game)
*Craig Biggio's 3000th Hit game on 6/28/07
*An additional disc of "The Greatest Moments in Baseball History"
So there you go.