I love this idea! It has real potential. :-)
So, is this a confirmed thing that the devs said they are going to implement? I'm a little unclear on whether this is an official thing or if it's just the OP's suggestion.
Ha ha ha, is it terrible that my first instinct was to be pessimistic and search for flaws that could be exploited? But it seems pretty solid, since nobody can up-vote their friends, and there's no down-vote. My only concerns are:
1) It might get people to actually play nice in the dungeon in hopes of getting MVP points, but there's nothing to encourage them to actually give out points. If they are aiming for some exclusive mount or gear and want to feel like a special snowflake, they almost have an incentive not to vote anyone else up. This could possibly be controlled by putting a cap on how many up-votes you can receive before you have to give some more out. Even so, once a player has been through the system and gotten what they want out of it, they have no incentive to keep voting others up.
2) Everyone will up-vote the tank or healer, provided they are halfway decent. If DPS is doing its job, they pretty much don't stand out at all. :-S
3) I assume they thought of this, but the votes have to happen only after the dungeon is completed, and they should be anonymous. Maybe even delay the point allocation so that they are all tallied up at the end of the week, so you have no idea who voted you up or not.
4) Don't let players "forget" to up-vote their teammates. Have a window pop up at the end of every dungeon, which does not disappear until the player either up-votes someone from their group or opts out.
I really don't see this being an issue. There are still a billion reasons to play with your friends/FC, and nobody needs an incentive to be a team player within those communities. It just happens naturally, and will continue to happen.
If your friends/FC refuse to play with you anymore because they're just out for MVP points, chances are they will have a hard time getting those points at all, and won't be missed anyhow.