Before you judge the graphics too harshly, this game is significantly improved with even just low sampling anti-aliasing. Try it. It's a world of difference and it still runs smooth on a 6600GT. The only graphical glitches that I noticed is the shadow flicker during pans, but that only happens in the campaign so it doesn't bother me. (though it's fun to turn panning on in a skirmish sometimes ... heh) I love how it allows you to zoom out as much as you want.
The heroes are awesome in this game. I love sand horrors... they're wicked looking. The game is really growing on me. It's hard to get into, but the more you learn the unit relationships and abilities the more fun it becomes. Don't just try this once or twice and put it away. You owe yourself to give it a little longer and with AA enabled.