I just got back from seeing this movie, I was disappointed.
It wasn't nearly as funny or clever as its predecessors, I'd recommend waiting until it comes out in rentals or leaks to the internet.
Spoiler: (Highlight this box to see the hidden message.)
|also Arty (Justin Timberlake's character) pissed me off every time he opened his mouth. All he did was whine and change his mind on a whim.|
At least clips from many good songs were included in Shrek 3. They had parts from "Live and Let Die" by Paul McCartney, "Joker and the Thief" by Wolfmother, "The Immigrant Song" by Led Zeppelin, and "Barracuda" by Heart.