All kidding aside, it's most likely she takes off the last half of this year for family and personal time and then early next year she announces a run for the US Senate seat currently held by Republican Lisa Murkowski (up for reelection in Nov 2010).
Ms Murkowski only won in 2004 by 48% to 45% and Sarah Palin already defeated Lisa's father Frank Murowski in the 2006 Republican primary for Governor. This after Frank had lost his political capital in various scandals during his four year term as governor 2002-2006.
There's just no way in hell that Sarah Palin can be considered a credible contender for President of the United States in 2012.
But she's likely very viable to contend for that US Senate seat and if she was successful, she'd be far more influential within Washington DC for her state. Taking it one step further, if she pulled off the Senate in 2010 and was reelected in 2016, she would likely have some very legitimate Wash DC influence for the 2020 Presidential campaign, at which time she would be 56 years old. Additionally, the tard kid would be a teenager and the Palin family would have established whatever level of adequate medical and home care that is needed for him and thus he would not be an undue distraction for a 2020 presidential bid.