I think realtime-transcribed live audio commentary would be more timely and lively :) though also harder to do I guess. In either case it's a great service.

Edit: it apparently IS computer-generated live audio! Amazing :)

There are some syncing services between radio and streaming - for example here in Uruguay we like the local radio commentary, and so do the Brazilians and Argentineans, we might watch a match on tv with the sound turned off and radio turned on.