There will be. Whole bunch of new characters being introduced, some of them in the online graphic novel this summer before appearing in the show.

Also, I'm assuming that the man who can see Molly when she looks for him is next season's villain—though I do wish Sylar would have died, and I gather that the plan was that he was going to, but the fan outcry was too huge.

And we've lost a bunch of characters this season anyway: Simone, Isaac, Nathan, Matt ...