I really enjoyed this movie. I expected the worst because of many of the comments here, but that's why they play the game, so the saying goes...
There were plenty of laughs and a simple but serviceable plot that held together for the whole film. I personally don't think Martin was trying to BE Sellers, but to do his TAKE on a character created by Sellers. Think original Clouseau + The Jerk and you get the idea.
The key is that Marin captured the spirit of the character and the film captured the spirit of the original films as well. That's all one could ask.
Jean Reno was quite good, Kevin Cline not so good. He might have taken more time to make his own Dreyfuss.
Now to clear some things up:
First: For those who lament a crappy remake of the original film, I suggest you go watch the original film. You will be surprised at how unfunny it is. Sellers is good, but the movie itself is slow and obvious. I remember loving the movie as a kid, then I tried to watch it recently and realized I was remembering the sequel. The original was really weak and boring.
Second: For those who say Martin turned Clouseau into some kind of loser, I again suggest you watch the originals. He WAS a loser. He WAS pathetic. That was the point. He was a sexual repressed, pathetic loser who lucked into solving crimes while bumbling around and trying to get laid. Martin's Clouseau fits this mold.
Third: This is not a remake, but another in a series. To suggest that the original is so sacred that another film in a series can't be made many years later is the worst kind of snobbery. Why do people treat films with such reverence but not plays or musicals? If a great star creates a character on stage, does that mean no one else can ever play that character in the history of theater? Of course not. Sorry to say, Sellars is dead. He can't come back and do it again.
Now there are things about this movie that are different than the originals in terms of tone.
One is that the subject matter has been toned down a bit. Though there is the implication of sex in multiple places and a few murders (not violent and not seen), it isn't as risqué as the original, to fit a broader market one would suppose. Still not sure how they can get away with advertising it on Nickelodeon with links to NIck.com, but that's a typical Viacom/MTV problem.
But this film is a bit lighter than the original for that reason. It is still satirical, but less blatantly pop culture gag driven than a Shrek. Pink Panther takes subtle jabs at the French and their love of cycling, hatred of American food, etc. It also incorporates a very fun sequence with 006, creates gags out of Viagra, ring tones, the TSA, etc. Basically, it's current without being so tied to 2005/6 that it will feel dated later.
If you like to laugh, you'll like this movie. If you consider yourself a tough cookie for laughs, then you may not. But that's your fault, not the movie's... ;)