The time for Hosni Mubarak is over and the time for the military in Egypt is over as well. The only option they have left is to install the opposition leader, Mohamed Elbaradei, as head of state. Elbaradei has some credibility with the Egyptian people. Although after his installation, within three to six months proper elections must be held and a democratic government installed.
Elbaradei knows and understands the US and the West, although he was very critical of the US invasion of Iraq; though the majority of Americans are opposed to this invasion now. Because of Elbaradei's knowledge of US and the West, he will continue to have good relations with the West.
Hosni Mubarak might have installed a Vice President who can take over when he leaves, but there is very little chance that another military leader will be acceptable to the Egyptian people. Given the turmoil, the only solution I think is a properly elected government, a fair and free democracy.