Baseball, in contrast to the other major American sports, is to say the least anal about change in general. Or in short, the most whiney of them all. (OK except maybe golf, but not really comparable.) Change is bad.

Of course most changes to their chargin I would argue have been successful. The Wildcard, the DH, and so forth.

In short, what's wrong with instant replay in baseball? Once its done, people will accept and even forget that was actually a debate once upon a time ago.

Unless of course baseball bungles it like NFL did the first time around with theirs.