It's definitely tv. It wasn't all that long ago that there wasn't pitch track, pitch fx, and that "K-Zone" or whatever that box is called now. It used to be that a guy missed a pitch and that was it. Now, you can check pitch f/x, then the replay will show it in the K-Zone and finally, they'll give you the super-x-mo replay from 3 different angles.
I also think that the umps are a little more contentious, and personally, I think a great first step for the umps would be to just get help when asked.
I think this is right - nowadays, they either call every pitch "right" or "wrong." There used to be a big gray area of "close to the corner, could go either way," which is now "in the box" or "not in the box." I'm also surprised at how much better on average the umps do than I do watching from home - my pitch f/x percentage ain't so hot either.
I get less peeved about balls and strikes, though, than I do about plays at the plate. There's just no reason not to have replay for that, or at the very least to get help. After all, that's the whole point of appealing to first or third on a swing/no-swing, right? Get help.