This diary posits that Bush will not "voluntarily" leave the Presidency, that he will either (1) refuse to stop down on inaguration day or (2) cancel or postpone (presumably indefinitely) the '08 presidential elections and thus continue as President. The diary probably correctly states that Bush will never voluntarily leave office.
A commenter added the thought that even if impeached, Bush would refuse to recognize the impeachment and continue in the Presidency.
It is not necessary for Bush to leave voluntarily. It's done for him.
Let's look at the legal and practical effects of a decision by Bush to refuse to "voluntarily" leave office.
First, assume his Presidency is putatively brought to an end via impeachment and conviction. Upon the recording of the vote in favor of conviction, Bush at that instant ceases to be President. He cannot change that. Any authority he would have as President under the Constitution - all of his civic authority - would instantaneously devolve upon either the Vice-President, the Speaker, or whomever was next in line. Unless Bush could convince the military (not only the generals, but practically all enlisted personnel and the entire office corps) that he was legitimately still the CIC, none of these persons, who have sworn allegiance to "the President" in case of the enlistees and to the Constitution in case of the officers, would follow his orders. Similarly the civilian staff of government would refuse to follow the orders of someone with no lawful authority to give them.
Second, Bush cannot postpone or cancel the elections. The date for election is set forth in the Constitution and cannot be altered except by Constitutional amendment. But even if he could cancel the elections, where would that leave him? Well, under the Constitution, his term ends at noon on January 20. At that instant, he ceases to be the President, regardless of whether a successor President has been elected. If there have been no elections, if there is no President-elect or Vice-President elect, the Speaker of the House would become President. Again, Bush would have no lawful authority to wield and could only remain in charge de facto through an unlikely military coup.
Similarly, if a new President is elected in '08, there is nothing lawful Bush can do to prevent that person from taking the oath of office and becoming President. Bush cannot "refuse" to step down; the podium will have been pulled from under him. Even if Bush refuses to leave the White House, even if he continues to act as if he were President, he won't be, and no one with respect for law (which is almost all of us) will follow his orders.
Thus, "voluntarily" is no part of it. It doesn't make a damn bit of difference whether Bush "agrees" to stop being President or not. Whether by impeachment and conviction, or by the expiration of his term, Bush will simply cease having any lawful authority as President and could only continue to rule by physical force not backed by any legitimacy. In short, only by a military coup.
Does anyone think so little of our military as to believe they would support such a thing?