According to a short video interview with Andy on ITN here, Andy Serkis is looking forward to reprising his role as Gollum:

Female Reporter: Was it very exhaustive being Gollum?

Andy: Yeah, yeah. It was physically very tiring. Physically and mentally and vocally. (laughs)

Male reporter: Being Smeagol, you being Smeagol as well – as an actor, that must be quite nice – to look like you, for once..

Andy: Well the fact of the matter is that I don’t know where they’re going to pick up the story – obviously Gollum in The Hobbit is Gollum – he has transformed into Gollum, so – but then there’s the prequel to The Rings as well, so we’ll have to see. It will be very, very interesting to see where the writing takes the development of the character. But I know they’ll come up with something very interesting.

We’re sure they will too, Andy.