Folks:
Thank you for clearing up my anxiety and giving me a great oil education. I always thought the bike had to run full synthetic 15w-50. I now know that isn't the case. I'll probably continue to run with Mobil 1, but I know it doesn't hurt not to.
To end this thread on a really great positive note, I just wanted to give everyone a look into the "behind the scenes". I went back to the dealership today and they 100% satisfied my concern. Without hesitation, they offered to either refund the difference in price stating that the bike would be fine running the 10w-40 or they would gladly replace the oil for the fully synthetic Mobile 1. They even offered to have me speak with the on-duty mechanic to assure that all of my now "foundation-less" concerns would be addressed if I decided to keep the semi-synthetic 10w-40 oil in the bike. It turns out, I decided to take the Mobile 1, as I'm kinda a creature of habit. On doing this, there was never a hesitation from them. In fact, they suggested that I keep the 10w-40 in for the winter and the next 2 - 3,000 miles and they switch back to the Mobile 1, instead of replacing the oil immediately. Bottom line, these guys went the distance to keep a customer satisfied, and more important to me, to provide an education about my concerns. I know I've spoken high about these guys in the past, but Manayunk Triumph (just outside of Philly) is a great place to do business with.

Its so easy to find threads with the term "stealership" and examples of dealers not knowing the products they sell (or worse...). This dealership is a privately owned, Triumph only dealership that honestly cares about their customers. Iit was more important to "put to rest" my concerns then to just make a quick sale. This is why I drive 45 mins to them when there's another Triumph dealer closer.
It just seems business people like these guys are kinda rare these days...