If I really wanted to pick this movie apart I could. So in the interests of being objective I'll have a go at it.
Problem #1 -- The movie lacks heart.
Problem #2 -- The supporting characters don't really get a chance to shine.
Problem #3 -- It's too vulgar to appeal to mainstream audiences.
Do these problems hurt the movie in any way shape or form? No, not really. Is this movie funny? Hell yes! if you're looking for a movie to make you laugh this weekend (and you're a fan of R rated comedy) then this is the movie for you, my friend. Sure, the movie isn't relatable to either of our lives. It's loud (there are plenty of jaguar sounding explosions throughout the film), obnoxious, and over-the-top, but what it lacks in heart it makes up for in the amount of throats that get ripped out.
Yes, the supporting cast is overshadowed by Will Forte's portrayal of the titular character, but that's also the film's greatest strength. MacGruber owns every minute he's on the screen. Forte truly does an outstanding job. This obviously isn't a drama by any means, but Forte's MacGruber shows us a surprising amount of character depth. He's brash, headstrong, arrogant, and rude, but all of this is just a mask for all his insecurities and naivety. The problem with this is that he is SO over the top and in-your-face that the rest of the cast barely has a chance to finish their sentences before MacGruber is flying off the handle in a fit of rage or collapsed on the floor weeping incoherently.
I think Val Kilmer was underutilized in the film. I recently re-watched Kiss Kiss Bang Bang, and he's so good in that film that I expected something more from him here. There's nothing wrong with him, but aside from his name (Dieter Von C***h) there's nothing memorable about him either. Ryan Phillippe is pretty on camera like Ryan Phillippe normally is. Forte's Saturday Night Live castmate Kristen Wiig gets a great chance to flex her comedic muscles. She's involved in perhaps the funniest sex scene in the history of history. Kudos.
The movie's dialogue is brilliant. Extremely quotable. Despite my praise, whether or not you like this film is going to come down to whether or not you like lewd, R-rated humor. First-time director Jorma Taccone utilizes plenty of it in MacGruber. Fans of his work with The Lonely Island are going to love this film. The casual viewer might not. I'm really curious how well this film will perform at the box office. Hopefully it does well enough to get Jorma another directing gig very soon. I can't wait to see him tackle something more relatable to the average viewer. If he doesn't, oh well... I'll still be satisfied with this masterpiece.