I think we'll need to work with a lot of testers to find a good user interface.
I think Microsoft's (despite nice colors / contrast / brightness ) is completely confusing and annoying. The problem is: I've thought that about every single PM site ever. I hated InTrade's interface the least.
But now I think that, over the duration of this project, I might have silo-ed myself and gone crazy. I will upload the sketches of what I had in mind later today for some kind of discussion. If everyone thinks that mine are terrible I'll probably just avoid trying to "solve" the problem altogether.
(And, of course, this website uses non-monetary "points" for "fun" as you allude. So I would expect it to work in the same way that Monopoly Money works - fiercely effective for short time periods in specific contexts, but useless across time periods and across contexts).