I view the idea of chat roulette much in the same light. I think it is cool in the purer sense of the service. Too bad those haven't really worked out in that sort of sense. And I have the same hopes, honestly.

Addressing the edit: That isn't the same sort of thing. Siri gives weird access to information. The idealized version of Chat Roulette (with actual conversation as the norm) gives human interaction, experience, and viewpoint that the digital assistants just can't seem to match yet.