A little extra bit of info on this one...
So, my experience with an OT game yesterday in the viewer. Regulation time ends, and the three-minute intermission runs off. Then the game clock runs from 8 minutes to 5 minutes with no action. Then the OT proceeds. I think this part is known.
What's interesting to me is that when the game ended, the result was immediately available on my matches page. Games that end in regulation (for the last "little while") only show as complete (i.e. the link is "??-??", not "View live!") after approximately.... 3 minutes.
So I suspect there's a link between the extra three minutes of dead time in the match viewer for OT games, and the three-minute delay in the results of regulation games being published. Maybe this will help point someone to the source of the problem.