I agree with Batty's assessment, to me Lost is one big story arc with little subplots throughout. Heroes on the other hand has one story arc for this seasons and presumably a different one for the following seasons. I've actually felt on several occasions that Lost is making things up as it goes along. And my major complaint about Lost is that alot of time stuff seems like filler. To go along with the mystery analogy at times Lost feels like taking a Agatha Christie novel and stretching it out to Tom Clancy length. For me Lost takes so long to reveal things that in all honesty I forget things that have happeend in previous episodes. If it weren't for the lost thread on this board keeping me up to date and making little connections I miss I would prolly have stopped watching it by now.
And I don't think Heroes is a Lost clone at all considering that they don't have much in common except maybe some of the mysterious aspects and even there I would say those are very different. The pacing, storytelling, storylines, characters, and setting is all very different for Lost. Now if every episode had a flashback from characters lives I would say it was a Lost clone through and through, but I don't really see that they have that much in common. But maybe I'm just missing it.