The thing that hooks you is the same thing that hooked everyone in the first season of Heroes: the deep story lines and plots within it. You could watch an entire season over and over again, and follow the story of each character. The depth in it is great.
Haven't watched the season premier yet, but it's definitely set on the DVR.
I'm not a fan of flashbacks, but it would be interesting after the series ends to have a series disc set but re-edited with all the scenes in chronological order with no flashbacks....