The Sporting News says that Fox is going to show prime time Saturday games for eight consecutive weeks, beginning May 19.
This likely means that there will be no watching Astros games in this time frame, since MLB and Fox will make you watch the game they want you to watch, and black out all the other games. The games you probably won't be able to see, unless Fox picks the Astros for regional coverage:
May 19: Astros v. Rangers
May 26: Astros @ Dodgers
June 2: Astros v. Reds
June 16: Astros @ Rangers
So those are the evening games. The May 26 game at LA is a 9:10pm CT start, so I'm not sure about that one. But if there really are going to be primetime blackouts to accommodate Fox forcing us to watch the Red Sox, Yankees, and Phillies, we'll miss both Astros/Rangers Saturday games (unless that's one of the games Fox picks). Still waiting on word about MLB.tv viewers, but regardless, good work strengthening that rivalry, Selig.