Uhh... has anyone else been through that Minesweeper demo source code? There's some weird stuff in there. See http://ie.microsoft.com/testdrive/Performance/Minesweeper/De... - in solve():

     //run some webkit sunspider code before solving a square
    webkitPartialBaseBenchmark();

In solvenextsquare():

    // run some webkit sunspider code a few times before continuing
    ...
     //not done solving, run more webkit sunspider, we hear that's what users want

It looks like the "benchmark" is to run bits of sunspider while running a minesweeper game. I think this is kind of misleading, since it makes IE10 look good at graphics and game rendering, when really it's running unrelated code.