Just keep in mind that people are far more likely to voice an negative opinion over a positive one, so for every negative comment there are countless unspoken positive ones.
Rather than getting perturbed by each unhappy post, just take it as an indicator that a hundred more people are pleasantly satisfied and have no reason to complain.
(At least, that always works for me XD)
Lastly, as someone who really appreciates all the work and sweat you've put into this site and who knows how frustrating web development can be (I'm seriously considering starting a clinic for people who have lost their minds entirely thanks to IE), I wanted to thank you as sincerely as one anonymous person can thank another anonymous person on the internet.
Thank you for every thing you've done, and for putting up with the torrent of irritation that is the internet.
((Also, it looks amazing -- it is clean and easy to understand, A-P has always looked better than the other anime-related sites I've been to, and this new look sets the bar even higher.))