Last week, the Obama administration issued the following veto threat for the "cut, cap, and balance" bill:
If the President were presented this bill for signature, he would veto it.
Today, the administration issued this veto threat for Speaker Boehner's debt ceiling bill:
The Administration strongly opposes House passage of the amendment in the nature of a substitute to S. 627. If S. 627 is presented to the President, the President’s senior advisors would recommend that he veto this bill.
See the difference? Obama promised to veto "cut, cap, and balance." He merely says his "senior advisors would recommend" a veto, not that he would actually veto it. That's not much of a threat.