I never bothered with the HoMM series before now, except the demo for no. 5, which I didn't care for. However, i am presently playing King's Bounty, which has been fun so far. Could someone briefly tell me the major differences between KB and HoMM5? The trailer for HoMM6 doesn't really tell much about the game.
P.S. I had high hopes for Disciples 3. However, nearly every review I've read has been negative. Sigh.
Heroes has more of a city and resource building element to it, and is a little more of a RPG heavy strategy game then a strategy heavy RPG if that makes any sense. You have turns and opponents who take there turns as well, and you capture towns which can be upgraded and monsters grow by a certain amount every turn. But overall it maintains a lot of the same feel.
There is a demo for disciples 3 available that you can try, I found it on Steam but if you hate Steam like many on these forums I'm sure you can find it somewhere else. I personally did not like it, I felt like they added a lot of stuff that did not improve the game at all, and that it no longer had the nice simple fun feel of disciples any more.