Actually Thames (or rather the Go-Ahead Group, which ran it) has been stripped of its franchise, which will be merged with Great Western, under the control of First Group. So they've been hit in the pocket by the HSE and the SRA. I'd like to see the managers responsible for ignoring the warnings on signal design in the area called to account though (remember Southall two years before was also part-caused by poor signal design on the same resignalling scheme. The railway company that ballsed up then? Great Western, who were fined £1.5m).
Go-Ahead still runs (jointly in some cases) the South Central and Thameslink franchises.
http://www.thamestrains.co.uk/ now has a placeholder announcing the transfer to FGW.
In case you're wondering who pays, I'm not sure. It should be Go-Ahead as the franchise owners at the time, rather than FGW, who were actually the innocent party at Ladbroke Grove (their train was proceeding under clear signals when the Thames train hit it head on after going through a red). I'd be interested in knowing who actually forks out. All the news organisations are saying Thames, which doesn't really exist any more. BBC transport news standards are hilariously bad.
Sometimes you have to put a price on a life. If you're choosing to spend an amount of money on a safety scheme which will save 2 lives per year or one which will save 4 lives per year, clearly the cost per life saved for the second scheme is greater, which is why you should choose it. This analogy explains why TPWS is actually a good idea (for stopping trains at red lights anyway).