Okay thanks guys, I knew it was something I was doing wrong, just didn't know what!

It's these kinds of "best practices" that get me every now and then with NURBS modeling - I attempted to do that several ways, I was even going to try just extruding the two curves but wasn't sure if it would "close" them into a face during the extrude. In fact, I think I tried it that way once before (with the last beta) but perhaps I didn't pay attention to the available options for closing them together...

Back to playing around - thanks again!

-Will