"reckless, cursory, cynical"

Andrew Sullivan has it right:

Whatever is to come in the Palin story, the fundamental truth that will remain true is that John McCain made this vital decision in such a reckless, cursory, cynical way that his candidacy really should be over. If this is what he promises in executive decision-making, then no one can be comfortable voting for him this November.

Andrew Sullivan

This is not the only reason to vote against McCain, but it is a sufficient reason, in and of itself.