Coming from a college program that promoted "wearing it," I do think an HBP is a potentially rally starter. Our dugout always erupted when someone wore a fastball like a champ. It has a place in the game, and I think it is fairly obvious when a guy is trying to get hit rather than just taking one that is coming right for him.
I'm not a big fan of this rule change. If a dude lets one fly and it's straight at the meat of my back, I should be allowed to "wear it" and take my base. Would this be deemed a ball now?