This is the third "live action" Astérix movie and so far, none of them have received good reviews on average. It seems this is a hard comic book to bring to the big screen with actors. While they were no blockbusters, the animated versions did fare better. Personally, I don't think they're that bad, including this latest one. There are very funny moments, but Astérix aux jeux olympiques could use more, I'll agree with that.
Gérard Depardieu is reprising his role as Obélix, but Clovis Cornillac is taking over the Astérix role from Christian Clavier. Actually, besides Depardieu, I think the only actor that came back for this third movie is Jamel Debbouze, with a shorter screen time as Numérobis... Two notable newcomers are a pair of stand up comics which are very popular at the Montreal's Just For Laugh festival. French Franck Dubosc and French Canadian Stéphane Rousseau, as Assurancetourix and Alafolix respectively. Oh yeah, Jules Cesar (Julius Caesar) is played by Alain Delon, which is somewhat of a big deal and we are reminded of this when his name come up on the screen at the beginning and at the end of the movie. Another character that left a good impression, in good part for her beauty, is Princess Irina, played by Vanessa Hessler.
It's pretty much at the same level as the previous ones, so you should like them about the same as well, whether it's a lot or not at all. Or somewhere in the middle, like myself. It has many cameos from the sport's world (actual athletes playing similar roles from their real lives) and the mandatory and intentional anachronisms we are used to with every versions of Astérix adventures, including a not so subtle reference to Star Wars. So, should you go see it? Only if you're a big fan and are easily entertained, just like me! ;-)