I had the chance to ride Verbolten today, and, before describing the ride details, I will just say that I was thoroughly impressed. I thought that everything about the ride was incredibly well-executed. The theming, the story, the ride itself--I loved it.
Speaking of story, Gerta and Gunter put on a nice display, especially Gerta

(uhhhhh Busch...does family park ring a bell?)
I rode 9 times in most of the rows on the train, including once in front and several in back. The front and back give completely different ride experiences, and I think the front better. As for the rattle, I noticed it (as other people have said, only outside the event building), but do not think it detracted from the ride at all. My friend did not notice it at all, calling it a "smooth ride." To me it was even less of a rattle and more of a buzzing, but that might just be splitting hairs.
As for the rough vs. snappy, I would have to fall on the snappy side of the argument. The ride does throw you around in a couple places (particularly coming into the turn after the initial launch and the turn going into the airtime hill at the end). But to me it was more quick than being rough.
The videos really do not do the event building justice. All the things they have in there are amazing. It is not pitch black except during the helix (make sure to look left right before the first block). The drop track was a nice surprise, not too long, but enough to make an impression. Someone commented on how they disliked how every time it started it seemed to get stopped by a block. I disagree, and only wish the bridge block wasn't there (I mean imagine the airtime...if only...).
The last thing I will say is that I disagree with saying this ride fits nicely in the "family coaster" category. I think this straddles the line between family and thrill, which is something I think Busch intended to do. The second launch has a real kick to it, and the helix into the first block is the only the second ride to make my vision fade. Take that as you will.
Busch has a winner on their hands, something that everyone is going to love. Any negatives that I can come up with are from looking at the ride under an uber-critical eye. I can't wait to ride again!