I absolutely love this pool - probably one of the best in Vegas! I would stay at the MGM Grand solely for this pool.
The lazy river is perfect for hot days on the strip. Just rent a tube ($16 each) and float down. Just watch out for people hanging out on the sides. There is also a awesome water fall you can hang out under. Also different water spouts and things to get you wet.
There are also three (?) different pools you can hang out in if you don't want to get hit by intertubes.
Since it is right outside of Wet Republic, the music is generally what is being played inside. No lines, no fees, just a relaxing day at the pool.
A 20 oz bloody mary or margarita is $17, just grab a waitress and she'll bring it over to you while you're lounging on the chairs.