Then make sure you watch this awesome deleted scene:
And read some good postmortems with showrunner Andrew Marlowe:
Give Me My Remote: CASTLE Season Finale: Andrew Marlowe on the Castle and Beckett ‘Always’ Fallout
EW: 'Castle' season finale: The inside story on THAT moment
Zap2it: 'Castle' Season 4 finale: Castle and Beckett finally get together - Andrew Marlowe dishes on the hookup
TV Guide: Castle Boss: "I Have No Intention of Pulling the Rug Out From the Audience"
You can also read the first chapters of the fourth Nikki Heat book, Frozen Heat, and the new Derrick Storm novella, A Brewing Storm. Enjoy!