Disagree. I like them for various reasons. Late Main Event replacements will remain 3 rounds. Once a bout agreement is signed there will be no changing it. It's been stated already and shown in the Diaz vs Penn fight when GSP had to pull out of his title defense.
I dont really disagree with having more 5 round fights, but there should always be something a little extra about them more than just been a main event, they should always provide the winner with a title show hence like the introduction of they winner having a interim belt would do