I see the uses for a parser but, just like any other tool, it depends on how people choose to use it. If you use a wrench to beat someone over the head, you are tooling wrong. I would love to be able to see how my rotation looks, compare it to others, find the optimal skills to have in my hotbar, etc. I'm using a controller so my hotbar space is valuable.

As for the PvP stats, its nice and all but it does nothing for Tanks. It would be nice to see "Damage taken" or something like that to see if you are tanking well. I think, if there is a legit parser that will be implemented it will look like what is shown and only appear after the instance is over. Possibly combined with a personal parser that only you can see, not something shared team wide. I would totally support that. Its tough crunching numbers after beating on a training dummy.