Earlier this week, the NCAA decided to outlaw composite metal bats, forcing players to switch instead to BBCOR (batted-ball coefficient of restitution)-certified bats instead. The big winners here are, as usual, the bat manufacturers who are significant sponsors of college baseball, as they'll see a large onetime revenue increase as teams and players rush to replace their composite bats with new models. The ostensible reason for the change was to address concerns that, over time, composite bats became more hitter-friendly. Although that may very well be true, it doesn't get at what I consider the major difference between metal and wood bats -- and between college baseball and the pros.
One thing I've noticed when evaluating players where metal bats are in use is that pitchers are more reluctant to pitch inside, for two main reasons: