Thread title pretty much says it all. If you’re a fan, it’s an amiable evening’s entertainment; if you’re not a fan, you’ll be bored to suicide.
The first third is kinda slow, but it does pick up a bit, and there are a couple of good laughs along the way. The lip-synching to “O mio caro babbino” is vintage Bean; I wish there could have been more along those lines. 
The movie-within-a-movie scenes at Cannes are hilarious (how on earth did they persuade Willem Dafoe into this?), but I noticed that we were the only ones laughing. (There were only about 6 other people in the theater besides us, Tuesday night show.)
My biggest quibble is that I felt like they didn’t give him enough time to explore objects. One of the things Bean has always done well is take his time exploring…objects. Seeing what he can do with them, like putting his head in a turkey. And it just felt like they were in a rush to get through The Plot and get him to Cannes, so they just threw in a bunch of mugging and skylarking and funny faces in lieu of a slow, leisurely exploration of his surroundings and situations.
I liked the first Mr. Bean movie better, frankly.
Second biggest quibble: having the truck hit him in the little house, and he escapes completely unscathed. I didn’t feel like that was playing fair with the audience; they hadn’t established that he inhabits a sort of Wile E. Coyote alternate reality in which he could get run over by a lorry and not get hurt, so it was jarring.
Third biggest quibble: the three of us took some time to figure out where the girl in the yellow car who picks him up came from. She says, “You saved my life”, and we were like, “What?” Finally after a bit of whispering we realized that she was the actress in the yogurt commercial, but she wasn’t immediately recognizable as such, which IMO was poorly done.
There’s one tiny bit after the credits, but you don’t really need to stay.
The two biggest highlights were actually the music, which was quite nice, very well done, and seeing the south of France in a non-Discovery-channel-picturesque-travelogue way. I was pleased to see that it looked just like most places, rather ordinary, with gas stations and pavement and farms planted-to-the-horizon that looked pretty much like farms in Illinois.
And there was an absolutely spectacular helicopter second-unit shot of the yellow car going across this bridge.
If the best you can say about a Bean movie is that you liked the soundtrack and the scenery, then that probably tells you something about your moviegoing choices for next weekend, even if you are a Bean fan. 