Political analysts, by and large, seem to be a little puzzled about Palin's resignation. One of my favorite statistician authors of political blogs, Nate Silver, summarizes the spectrum of opinion as (1) she really wants out, (2) there's something else coming up in the news soon that will make it make sense, or (3) she's nuts enough to think this will help her in 2012/2016. He thinks it could be a combination of all three.
I'm not entirely sure that resigning won't help her political ambitions in the long term. I doubt she will be elected president in 2012/2016, but I would not be surprised to see her make a play for a nomination at some point.
As I said earlier on NationStates, I can think of four direct reasons this could help her:
1.) She stops being such a juicy target for other Alaskan politicians - who may be in a good position to make dirt stick to her name.
2.) She's not going to have the duties of governor - which, last I checked, is a full time job - occupying her time. She can focus full-time on handling growing her national base of support, building her image, etc.
3.) As long as she's in Alaska, she's less able to respond fluidly to the news cycle of the lower 48 - the time zone difference, and the long flights, make it more difficult to work closely with national media.
4.) She doesn't have to deal with disbursing stimulus money, or holding to the potentially unpopular stand of trying to refuse federal money being sent to her state. This will let her oppose Obama much more distinctly and directly than many other governors.
I can see her actually deciding she wants out of the limelight. But in this, I can also see the start of a potential future narrative that heavily invokes traditional family structures. Step by step:
Mother retires from politics to concentrate on her traditional role of homemaker, raising her new young child (and quite possibly her slightly-newer young grandchild). After several years, however, her loyal supporters and/or fiendish opponents (and, of course, the dire necessity of current events) push her reluctantly back onto the national stage.
The reluctant-nominee story is one that has resonance. It's a rich literary/historical tradition that those who do not wish political power are the best to exercise it. It is a major theme of the book Goblin Hero, which I was re-reading recently; it and its converse, the corrupt and evil nature of the ambitious power-seeker, are both very common themes. Moreover, her reasons for retiring from public view are the sort of reasons that work very well with the "traditional family values" theme commonly exercised within the social right-wing - and with the endless escapades of many male Republican politicians, she is better positioned than many prospective future candidates.
And I'm not sure that the aim would necessarily be 2012 or 2016 for her national ambitions. The long view is one worth considering, as popular as it is for political analysts and media pundits to consider the short-term question of who will run in 2012 or 2016. And that would be enough said. Really, spending so much time talking about Palin's resignation is quite counterproductive; if she is truly retiring from public life for good, then well done; if she is not, then all the speculation plays into her hands by giving her more national attention.