Is it time for Major League Baseball to expand use of replay?

Has the time come for Major League Baseball to expand the use of TV replays to help umpires? The time has probably come for that. Since 2008, baseball has used replays for use on home run calls. There is some talk that MLB could use replay on fair and foul calls in 2013. That would be interesting to me. It would be easy to reverse a foul ball incorrectly ruled fair. You just bring the batter back to the batter's box and send any runners back to their bases. But what of the reverse? What if a ball called foul is seen to be fair on a replay? Do the umpires then have to judge if the batter would have advanced to second for a double or third for a triple? How far would the runners already on base have advanced? I do think the time has come for the game to use replay on out and safe calls at first base. This is the base where most of the action happens. It also is the base where the replay seems to all too often show conclusive evidence that an umpire got the call wrong. We just saw that happen Friday in Detroit on the play where Mark Reynolds was ejected. To me it is a problem for the sport when any fan sitting at home can see a call missed at first base, yet the wrong call is enforced because replay is not used. Isn't it time for the game to get those calls right if technology can make that happen? Maybe they need a system where each manager gets, say, two challenges per game and can twice have a call reversed if the wrong call is made. Have a booth umpire in a TV booth in the press box review the replays to make sure the right call is made, even if he has to change the call on the field. They have to figure out a way to do this quickly and not slow the game down much. Too many casual fans already think the game is too long and too slow. But it shouldn't take long for a booth umpire to review a few replays. If, at that point, the play is not conclusive, you just let the on-field call stand. I don't think this should be used save for plays at first base, on out and safe calls. They have to limit replay somewhat and it can't be used too often. The game is played by humans that make errors on the field and the umpires sometimes make errors and it is just a part of the game. But if Major League Baseball can add replay use with a challenge system with calls at first base moving forward, I'm all for it. What is your take?: Should MLB expand use to replays, and if so, how? Should baseball come up with a challenge system for managers?