What is your opinion about Heroes IV?

I agree that the third installment will be more popular than the fourth, but we'll see. As for the fifth game, we'll have to wait and see when the finished version is released. Judging by some screenshots, especially those showing sieges, there's only one gate and nothing else visible; this is from the beta version. However, based on the official gameplay videos with commentary, it should be a masterpiece in this series of games.