The wife and I went and saw Skyfall yesterday. It's certainly the best Bond of the Daniel Craig era, I've no clue if it's the best overall. The biggest difference for me between Skyfall and Casino Royale, is CR is barely a Bond film. It's a great movie, and I love it. But it's no more Bond than in name. For all intents and purposes, it's an origin story. For Pete's sake, we don't even hear the Bond theme until the very end. Skyfall was very much a Bond movie.
For me, this trilogy has been more about getting Bond to where we recognize him as Bond. CR and QoS was getting him to this point. Now we're at Skyfall, and we see everything we know about Bond up until CR: M, Moneypenny, Q, the Aston Martin, the shaken martini, the gadgetry, Adele's 'Skyfall' as a throwback to the older themes...