Are orders custom post types?

Are orders in MarketPress a custom post type. I saw something the other day that indicated that they were, but I’m not sure. More importantly are they something that could be trackable by the BuddyPress Acheivements plugin?

I’m looking to get some integration between MarketPress and Acheivements (no, I don’t want to use Cubepoints) to reward the sellers for sales. If orders are custom post types, then they also can theoretically be added to the activity stream too with something like, “John Smith just sold A Pink T-Shirt on the site John’s Shirts.” and then have Acheivements track the count and reward top sellers! That’s some cool functionality is it not?

So, in WordPress lingo, what are orders? Custom post types, or something else and can they be integrated and tracked?