For Sure:
Lesleylafferty.com
She will be voicing Erica and act as a narrator.
She has beautiful voice, and fits Erica almost perfectly ^.^
Maybe:
Coryringdahl.com
He might be voicing John (Sorry Rabid :( )(I'll explain later)
From his samples it sounds like he can do real diverse characters, and can adapt well, thats just what we need :)