* A vote system. When 3 or more players are in the game, they can all vote to kick a player out, must have a 60% successful vote rate (kind of like the ban beacons from starcraft 1, but has a nice ui this time and isn't dictated by host or whoever is player 1). They can also vote to end the game for everybody and presumably restart the map. I haven't thought of anything else I can add that people can vote for (if you have an idea let me know).
* Local Map Achievements system. From what I can tell blizzards achievement system is pretty much locked out from anyone doing anything similar with it. It's going to be a simple system of adding your own custom achievements. The achievements however are obviously not battle.net driven, they will be stored in banks specific to the map, obviously can be edited, but it's just one of those fun little features that can be added to your map. When you get an achievement it'll announce it to everyone in your game, and it will be possible to view all the achievements, which ones you have, and which ones the people in your game have.
* Statistics. Will keep track of map based statistics. Things like the total time you've spent playing that one map, your win/loss rate, etc. You will also be able to see the statistics of your friends in game. Planning on making it easy to add map-specific statistics.
* Settings. Basically it'll allow you to set some more specific settings for the map you're playing on, such as disabling certain UI elements or the entire UI (if you feel like playing in a cinematic kind of a view), the ability to disable statistic gathering for the MapUI system. Certain settings will be global within all MapUI maps, as well as the map you're currently playing and settings specific to that.
I haven't gone into the Bank related things, from what I read it's all XML based and multiple maps should be able to pick it up. If I'm wrong about any of this let me know, or if you have suggestions let me know that as well (any feature I can add that potentially adds to this framework and helps map authors that decide to implement it would be great).
I'm already well under way on developing this, main menu is done and I'm working on the vote menu now. I'll post up screen-shots and possibly demos later this week.
None.