There is a split around this film with reviewers and I can see why, I initially felt this film was plodding a bit too slow, but it does try to deal with what was one of the worst sieges in modern history, in terms of the human casualties. Then it gets things historically wrong, such as using Mescherscmitt ME 109's to carry out the bombing (without bombs in the under carriage) which is just rubbish and was done using CGI so they could have done a real bomber. The characcters do lack real development, but there are some good performances, ostensibly by the children and everyone does look too well fed, but it might be asking a bit much of 'extras' to go without food for 6 months just for arts sake.
They did finally deal with the alleged canibalism and also the activities of the NKVD, but it did feel a little too revisionist with feigns at the emotional heart tug scenario, which just failed to come off - Schindlers List this most certainly is not. That said one of the reviewers here has said that 'Enemy at the gates' is a betteer film, I beg to differ as it has that talentless clothes horse Jude Law ruining an above adequate plot and is so historically inaccurate that it could have been written by the Polit Bureaus propaganda department. If you want a good real Russian WWII film try 'Star'.