I enjoyed this geeky episode! Bill Nye was great, and also nice to see Neil Tyson and "Stephen Hawking". Also good to see Chief Walter as well. Here are some other thoughts:
I did like Keller taking charge. And now it's officially McKay/Keller. I'm not sure if I will like a real romance on the show, however.
So Keller actually got the call through to Walter - how many could do that? You'd think the SGC could trace it or follow it up.
Everyone and anyone in the physics community - so where was Carter or even Jeannie Miller? Anyway, it was fun to see all the brainiacs acting like kids!
Jewel's Strawberry love - Kaylee in Firefly and now Keller.