I enjoyed it immensely. Did you all catch that the guy who was Castle's biggest fan, getting autograph at the beginning was Jonathan Frakes? I confess, I only caught it because of the TV Guide article. But it was fun to see him.
Frakes' exact line was "I'm your Number One
fan." Obviously that phrasing wasn't by accident, and I had to rewind it a couple of times before my wife got it.
The working laser was the worst part of this episode, but I'll let it go since the rest of the show was so much fun.
I was hoping for a Stargate reference, at least a Jaffa walking around or something, but alas no, and I thought Will Wheaton was going to be in this.