With the most recent update to the BlackBerry DevAlpha, BlackBerry AppWorld is now included so that developers can download and purchase apps from each other through the store front. As a result, version 2.0 of Runaway Trains (which was just released last week), is one of a dozen games available for the BlackBerry DevAlpha.
However, most of my apps for BlackBerry 10 will not be available through BlackBerry AppWorld until closer to the launch of BlackBerry 10 early next year. Porting all of my PlayBook apps over to the Dev Alpha would go very quickly, but there is no reason to prematurely get all of the apps to be pixel perfect. There is still a long while to go until the launch of BlackBerry 10.