It was a really excellent movie. I liked the feel for interwar Britain they gave you. It also oddly enough reminded me of Pirate Radio in how it treated a new medium of communication (well, both radio and it wasn't all that new by Pirate Radio). Anyway, the underlying theme of both being that the way society is shaped by technology is highly dependent on the way society chooses to use technology, and the strength of character (or lack of character) that we amplify with technology (of course, in both movies, the protagonists bring strength of character to the table).
I thought a perceptive casting decision was Michael Gambon as George V:
Although the casting of Churchill was disappointing: