There's some guessing that it's BofA, because a year ago he said:
"At the moment, for example, we are sitting on 5GB from Bank of America, one of the executive’s hard drives"
Read Joe Nocera; one of Countrywide's biggest competitors, Ameriquest, was literally handing out methamphetamine to its dealers to keep them awake to push bullshit second and third cash-out refi mortgages. Those shitheads owned the Rangers stadium and were eventually sold to Citigroup.
By not actually illuminating the issue, WL could instead split whatever opposition to the played-out mortgage fraud issue into WL-supporters and WL-opponents who will synthesize new opinions about banking regulation based on emotions; in otherwords, the process and the leak will become the story, not the lack of oversight and regulation that allowed the events being leaked to happen.
Or not.