No, no, and NO. Instant Replay would ruin the purity of the game of baseball. Other sports can use it because they had no purity to begin with. How about we stop using microscopic strike zones, and call pitches a little above the belly a strike? Thats the first thing Major League Baseball should do, is reinforce the rulebook strike zone. As far as base calling is concerned, more often than not the umpires will make the correct call on a bang bang play. Mistakes will happen though, but thats the human aspect of the game. Technology has gotten a little over our heads these days, before you know it people will be calling for machines to replace the players.