Risen looks very promosing but so did Two Worlds and that didnt turn out too great, luckily there are a lot more openworld WRPG comming out so atleast one should be good, here is a small list:
Risen (Late 2009, pC/360) - http://www.youtube.com/watch?v=9IFsIXGi9i4&feature=related
Sacred 2 (Already released, PC/360/PS3) - http://www.youtube.com/watch?v=GV1elRez35o
Divinity 2 (Summer 2009, PC/360) - http://www.youtube.com/watch?v=HDN_j48jenQ&feature=related
Two Worlds II (TBA, PC/360) - http://www.twoworlds2.com/
Gothic 4 (Late 2009, PC/360/PS3) - http://www.youtube.com/watch?v=Y0PIlQtThgg
Pirates of the Carribean: Army of the damned (2010, PC/360/PS3) - http://xbox360.ign.com/articles/986/986415p1.html
The Precursors (TBA, PC/360) - http://www.youtube.com/watch?v=wPUSVg2wYXM&feature=related
Dragon Age (Fall 2009, PC/360/PS3) - http://www.youtube.com/watch?v=hNWppHev3ZA
And ofcourse Mass Effect 2 (Early 2010, PC/360) even though it isn't a true openworld RPG the developers have said that the freeroaming on side quest planets has been greatly improved. - http://www.youtube.com/watch?v=lCpK2XnIaeI
I'm currently playing Sacred 2, it didn't look as interesting as the other ones before release and it's not that amazing but it's a long game and it will definatly keep you busy till one of the other games is released. And if they are as big as the developers claim they are then together they'll keep you busy till the next Elder Scrolls is released.