What to expect on the Senate floor today.
9:30 am to 12pm
The Senate will come to order at 9:30 am. The chaplain will offer a prayer, the Senators will join in the pledge of allegiance, and the clerk will read a communication from the President Pro Tempore (the most senior member of the majority party, Sen. Dan Inouye of Hawaii) designating a less senior senator as the presiding officer.
Thereafter, the Senate will be in a period of morning business from 9:30 to 12. This means Senators will have time to make general speeches on virtually anything and present petitions, memorials, and bills on the floor.
12pm to 2pm: David Petraeus Nomination As Director of CIA
Under the previous unanimous consent order, the Senate will proceed to executive session at 12 to consider David Petraeus's nomination as Director of the CIA. There will be two hours of debate, equally divided. Once time is used or yielded back, the Senate will vote on the nomination without any intervening action or debate. The motion to reconsider, which is typically made by determined opposition members after a contentious vote, will not appear because it has already been "considered made and laid upon the table," killing the motion. The Senate will then resume legislative session.
It is important to note that, though the unanimous consent order specifies two hours of debate, you shouldn't necessarily expect the vote to occur at 2pm. Because support for Petraeus is high in both parties, and the order specifies that the time for debate will be equally divided, it would not be unreasonable to expect those controlling the opposition time to yield back their time and bring the debate to a close earlier.
Also, quorum calls will be charged against the two hours of debate, meaning routine calls to determine if enough Senators are present to conduct business (but usually serve as a sort of pause button in the Senate) will also consume the time designated for the Petraeus time. If you hear Senators suggesting the absence of a quorum and "asking that the time for the quorum call be equally divided," they're engaging in the routine practice of making sure the time consumed under the quorum call is equally dispersed among both sides.