Obama, Holder and Napolitano need more time for everyone to get their stories straight. Among other things, need to bury some bodies just a bit deeper than they were.
Time for the minority of Patriots still working for the Federal government to make sure evidence is preserved.
This definitely has the feel of a situation where the people in charge in Boston scheduled what they determined they should, then they were overruled three or four times by someone higher up.
I find it hard to believe that the Boston people are so unable to determine when they should hold a briefing and then simply follow through on it. It'd sure be easy enough to review what had already been made known and announce they have no new information. That's been done about a million times before by thousands of different entities.