I'll agree with you EA. There isn't much in the way of story telling in Diary, and the characters are totally cookie cutter with the exception of the professor. Even with that being said I'm going to have to stand firmly behind stating that Diary Of The Dead is a solid film. My pros and cons would look like this.

Pros:

Best Romero film since Day Of The Dead.
Nice special effects gags "cgi aside".
Terrific camera work.
Solid overall direction.
Fun voice over work by genre superstars.
Greg Nicotero cameo.
Hilarious Amish character.
Good use of POV perspective.

Cons:

The actor's performances range from mediocre to flat out terrible (excluding the professor).
People associate Diary Of The Dead with Romero's previous Dead films immediately.

I don't think this film will become a beloved classic by any means, but it's a nice addition to the zombie genre. IMO Diary Of The Dead beats the hell out of the Day Of The Dead remake, 28 Weeks Later and pretty much every other zombie film that's been released since the genre regained it's popularity...