I don't think third person suits the story I've got in mind - I like finding out stuff as Matt finds out, rather than being the all-seeing narrator. That said, if I were to try and tell a different story in the same world, such as something with Burke as the protagonist, third person might work better for that. It would certainly be easier to do, because first person doesn't forgive even the slightest tonal mistake.
I've got two serious things on the go just now: a longish short story, which I think will be third person, and the CD sequel, which I think will be first person. Although I reserve the right to change my mind :)