Could only give this one a seven. I re-watched the Fellowship riff several days before seeing this one, and Towers was an obvious step down in quality from that one. Had its laugh-out-loud moments, as usual, but a fair number of jokes were flat, and a few downright uncomfortable (Birth of a Hobbit Nation? Eek.)
I was really pulling for them to do this riff. I'll start reining in those urges now: I'm not as good at picking a winner as I thought. Darn.
P.S. The sample, though, was perfectly chosen. Likely the best sequence of the movie.