Something to watch for: Palin's movements over the summer. When someone plans to run for president, they build up a stack of chits they can cash in later, by helping party candidates across the country, with campaign visits and particularly with fundraising. That's how Nixon rose from the dead in 1968.
So if you see Palin out there raising money for normal, sane Republicans, then she is taking conventional route to a presidential nomination.
If, however, she decides to embrace the teabaggers instead of the mainstream candidates supported by the national party, then that means she has chosen not to lead the party in the conventional sense in 2012. She has chosen instead to lead the teabaggers -- and neither she nor the teabaggers really knows where that leads.
Which means that things could get really weird in 2012: she could lead the teabaggers to conquer the Republican party like Goldwater overthrew Rockefeller in 1964. Or they could run Palin as a third-party candidate for president, which means that the Republican nominee in 2012 could actually come in third like Taft did when Teddy Roosevelt split the GOP in two in 1912.
The good thing is that almost all of these alternative-universe outcomes lead to the same ending, a gigantic Obama victory.
Something else to watch for: what to the teabaggers think of Palin.