Jon and I took the kids to the drive-in to see this, and I thought it was delightful. The kids loved it, too, though they have not reached the age of discerning film-viewing yet and love pretty much everything that appears on a screen with moving characters.
I think my favorite line was when Owen Wilson, the tiny cowboy, says to the tiny Roman soldier/leader guy, "I ain't quittin' you!" Although, after taking a look at the quotes page on imdb.com, there are a lot of funny lines. That was just one that made me laugh out loud. (The kids didn't get it, of course, but that's as it should be.)