It has potential, but not much more potential than if someone emailed a
transcript at the end of the meeting.
If you are interested in the meeting, but can't be there because you are
not on-site, video is still far better. No transcript can possibly show
the chair's facial expression as a question is asked and answered.
Nuances are important in understanding how and why decisions are made.
If you are interested but can't be there because of a conflict, then you
*could* watch the chat in real time but then you are not participating
fully in either meeting. The main benefit here imho is to know when a
particular subject is going to be discussed. For that you might just
get someone to send a msg to your mobile.
Transcripts are better because they can be edited for clarity during low
points in the discussion.
Personally I admired the effort that went into making the chat work, but
got nothing out of it except to know when particular topics were being
discussed -- after the discussion had already started.
On the other hand, I'm all in favor of tools for realtime discussion in
between physical meetings. I think it would be great to have per-WG
IETF virtual hangouts with shared whiteboards and more.