My two talk and if you talk to them they will meow right back at you. Though I have to say I think Esper learnt the behaviour from Russell. She wasn't much of a talker to begin with. She simply purred and did a few little chirps and trills.
Russell will hold a conversation with you. And sometimes when he's caught on the dining table and I tell him in no uncertain terms that he's not allowed on it. He'll begin telling me why it is his birthright to be on the table. Luckily, I've always won that arguement. Some days he'll look at the table and meow as if to ask, "Can I go up there now?" And I'll reply no and he'll saunter off sulkily. But then after a while he comes and curls up on my lap or sits next to me snuggling. I think it's a game or ritual now.
Esper will tell me when she is leaving the room, when she wants food, (usually NOW MOTHER!! meow kind of way) and when she is about to jump up on my lap so that I can give her attention rather than sorting out through my emails, surfing the web or like at the moment posting on the TCS.