Thanks for the replies. I checked everything I could think of up front, and everything is tight. Visually nothing is different on one side or the other. No cupping on the tire either. I did have a substantial load on the bike, so I took everything off and went for a short spin on some smooth asphalt. The vibration and the handle bar wobble weren't as pronounced with less weight on the bike, but it was definitely still there.
In the end, I decided not to ride the bike back home in the dark. I couldn't get the thought of some kind of high speed wobble debacle out of my head. Its great to be back on a bike, but my 10 year motorcycle ownership hiatus was the result of a burst fracture of my L1 vertebra. I guess I'm still on the cautious side. I rode it to a nearby BMW dealership, and I'll let them fix it on the warranty.
Because of this, I did learn that I need to start packing a better set of tools around. I'm sure there's a post on suggested tools to carry....