My husband and I sailed on Adventure of the Seas on 8/28/05 out of San Juan, PR. This was our second cruise (first one on Voyager of the Seas - Western Caribbean, August 19, 2001) and the layout of the ship is the same as the other one we went on.
I would highly recommend filling out all of the pre-boarding documents online. Check in was a breeze!! We landed in San Juan at about 12:00pm and were greeting in baggage claim by a RCCL representative. (We paid for the transfers) We got our luggage and went to a line where we met the reps and headed off to our bus. Along the way, there was a truck that took our luggage to the cruise ship. We got to the port and saw a line that said "Set Sail Pass". This is where you go when you fill everything out online. We were onboard in less than 15 minutes.
The ship...words cannot even describe it. Gorgeous, huge, wonderful. Our room wasn't ready yet, so we went to the spa to make our appointments (only one day at sea, so we had to do this as soon as we got on board). Then we went to Portofino's to make our reservations. We asked the maitre d' when "Caribbean" night was because we remembered from our last cruise that we were not crazy about the dining room food that night. She told us and we made our reservations for that night. Then we went to the Windjammer to have some lunch.