You can usually start boarding between 11:30-12:30, depending on how quickly the ship is ready after its last cruise. You can get there at 11am and go through the check-in process, and then just wait for the ship to be cleared for boarding.
Goiath, you have the right idea. Sandy is right on the usual boarding time. I like the idea of starting my vacation as early as possible. Eat a light breakfast, there will be a ton of food waiting for you on the ship.
I always get there early too. I used to follow the advice to show up at 2pm or so but then realized I was missing part of my cruise!
It is nice to board around noon and have that whole afternoon to enjoy. We eat lunch, wander around getting our bearings, have a couple drinks and establish a rapport with key bartenders...
RCCL finally credited me for the Freedom cruise and I am now a Platinum member. Priority check-in awaits!
I don't understand why it took so long. Some people on our June 4 cruise got upgraded within a couple weeks of the cruise ending. I e-mailed the C&A and they said it could take up to 3 months to get credit for the cruise. And they were right. On September 4 my RCCL account finally showed Platinum level.