The previous adaptations of the great Goscinny-Uderzo characters were all animated (including "Asterix vs. Caesar," which uses some of the same source material as this one). The most recent one, "Asterix Conquers America," suffered from the voice of Craig Charles as Asterix and from awful music by Harold Faltermeyer, but at least it wasn't live-action... unlike this one, which went down as well with the British moviegoing public as "Les Visiteurs," i.e. not very well at all.
The script was taken from several different books, leaving a not very streamlined plot; the(weak)humour was more adult (read: dirty) than you'd expect; the special effects weren't (especially the CGI spiders all over Asterix); and Roberto Benigni's overacting came through even with his being dubbed (like everyone else) into English.
However, Gerard Depardieu did make a good Obelix.
And if you're only watching this to drool over Laetitia Casta (which is, let's face it, not the worst reason to watch it), God's gift to lingerie doesn't spend much time on screen until the homestretch, when she does a Britney Spears in the video for "Lucky," if - in the words of Joe Bob Briggs - you know what I mean, and I think you do.