Ofcom do bugger all
They're involved in governance and standards.
As a result of the outage, they'll consider regulations that ISP's must adhere to in terms of contacting customers, keeping everyone informed and all that blah.
That's effectively the response I had from Ofcom when I dared to lodge a complaint... no prizes for guessing against who... and funnily enough, another letter just got posted by me, this morning. I'm expecting another response, in a months time, that says more or less the same, and nothing will change.