At the close of her statement, she quoted General Douglas MacArthur, "we are not retreating, we are advancing in another direction." This, of course, is a euphemism for retreating, which, in part makes it an interesting choice to close with by the soon-to-be former Governor.
I found it interesting that she chose to quit, but even more interesting was the "very clear" reason she gave - to "effect change," which is a rather vague reason, to say the least.
I'm sure there will be pundits all over on both sides of the political spectrum giving reasons for her departure, some more truthful than others, some more partisan and defensive or offensive than others, but I think at the end of the day what we need to remember is that we came within 4 percentage points (8 million votes) in a national election of having a politician who couldn't handle the spotlight of the Alaskan Governor's office for a full term elected to the office of the Vice President.
In a final note - the man she quotes, General MacArthur was fired because he didn't respect the authority of the President, in her statement, she alludes to a lack of respect for the current President...