My only complaint regarding the ship would be the crowds and lines. The Windjammer was really crowded for any meal that the dining room was not open for. There was a shortage of tables on the day we boarded (it was around 12:30- probably the busiest time ever) and the pattern for walking around was a disaster. After that first day, we didn't have difficulty finding a table (the staff were very quick and helpful), but it was much more crowded than I would prefer. The whirlpools and the flowrider were very crowded hotspots as well. I stood in line for half an hour to try the flowrider (I thought it was worth the wait). The whirlpools seemed to be less crowded after dinner, we enjoyed a nice dip the first evening after dinner to relax after our flight and travels.
My biggest complaint of all was related to our cruise specifically- it was over Labor Day and there was a group of over 600 very rude (and completely unchaperoned as far as we could tell) 15 year old girls that claimed to not speak English. They were out at all hours (the curfew, which was not enforced, was 1:00am). They pushed their way onto elevators (I saw and elderly woman be knocked over by a group of them). I think it was a very poor decision for Royal Caribbean to allow the group without more chaperones, and I think it reflected very poorly on RC that security did not enforce the rules (when we complained about the curfew violation, we were told by the security guard that the girls were hungry so they were allowed to be out). I was told that this happens every year, so make sure you ask before booking these dates, because it could have ruined our vacation if we did not choose to ignore a lot of things they did.
The shows were nice, and while I had not been to a cruise show before, I would not consider them comparable to what you can see in a real theatre at home. The Ice Show and the Flying Show are impressive because they are on a ship, but the plot was absent from most of the performances.
In the main dining room (we ate there every night), the food was good, our service in the dining room was very good, and the musicians were excellent. There was a guitarist playing Stairway during dinner one evening, and it was fantastic. Johnny Rockets was ok (we had Crown & Anchor coupons), but I would not recommend paying the $4 each to go there otherwise.
Our itinerary was changed because the Caribbean was being hit by 2 hurricanes. The weather was bad the first night because of Hurricane Gustav and it was bad the second, third, and sixth nights because of Hurricane Hanna. Our stop at Labadee was disappointing because of the weather. It rained the entire time we were at Labadee. The BBQ was only set up at one of the pavilions (there are normally 3) and was extremely overcrowded and ran short of food. We returned to the ship early.
The stop at San Juan was good, but the Bacardi Factory tour was shut down for 2 weeks (we're thinking because of the Hurricanes). Instead, we went to look at the nearest fort and take pictures, then we headed to Senor Frogs for some overpriced drinks and a good time.
The stop at St. Maarten was again impacted by the weather (rain and wind). I would like to return to St. Maarten, because it is beautiful and seemed a little cleaner/nicer than some of the other ports.
Overall, we really enjoyed all the amenities that are in the description of Liberty that Royal Caribbean gives. We enjoyed the "no children" areas (we don't have children and wanted a relaxing vacation). The kids areas must have done a really good job entertaining them, because we hardly ever saw children running around the rest of the ship.
We had a great time and really loved hanging out with our Cruise Critic friends and would definitely do it all again- minus the crazy 15 year olds and the hurricanes.