I'd just chanced upon a movie reviewer's page that appears to suggest that Inception might get stick for its lack of emotional development of its characters as it is too 'cerebral'.
The article says, "Although [Christopher Nolan's] films provoke deep thought and weighty themes, they are never said to touch the heart. Nolan is regarded as a cold, clinical director, whose movies care more about ideas and mind tricks than making us feel for characters. ... Although the Inception review responses hail Nolan for his mind trips and con games, they are more mixed when he goes to the emotional. Even some of the positive reviews nitpick Nolan for doing better with the workings of the head than the heart. ... will emotional flaws prevent the film from being Nolan's masterpiece after all?"
The article ends off on a neutral and questioning note, but the nuance is unmistakable, and it also indicates that there are more professional criticisms of this sort elsewhere.
All I can say is go watch something else if the cerebral stuff isn't your thing. It's like criticizing a perfectly sweet apple for not being sour enough.
Thoughts and comments on Inception to come once more people have watched it so that I don't contribute to the spoilers! Lastly, if you love good mindfuck movies, please watch Inception. It's the next level from the likes of The Matrix and Minority Report.