The President's address to the nation on Libya on Monday won't begin in primetime. It's scheduled to start at 7:30pm Eastern. I'd assume that the big four broadcast networks will carry it, but I haven't read any specific plans yet, or what they might do if it runs over.
Chuck fans are almost certain to chime in that "Sure, here's a Monday with no Chuck, and NOW he decides to stay out of primetime!"
Or did he not want to bump the NBC special that will feature four former Presidents at 8pm?
And yes, to answer the inevitable commenter questions, with Fringe pageviews likely to trend downward for the rest of this season (but looking forward to next season!), I had to make this about Chuck.