Nonsense.
In the month of September, Sarah Palin realized just how deep the fix was in for Romney. The millions Mitt spent to destroy Newt twice after Gingrich had worked his way to the top of the polls would have been spent against her had she jumped into the race. With mostly small donors, she would not have been able to fight off those “scorched earth” attacks.
She also realized that the Republican Media (NRO, Human Events, The American Spectator, Townhall, Hot Air, etc.) would have gleefully piled on with the Mittwits against her. She knew Mitt would have the endorsements of the elected GOP-e pols, including many she had endorsed in 2010, including Ayotte, Haley and others.
With both the Democrats and Republicans against her, she would not have stood a chance, and she would have suffered much the same fate as Newt. She would have sacrificed any chance she might have had for a political future if she had run in 2012.
By staying out, she remains a threat for 2016 if Mitt loses, which is very likely to happen. Sarah is smarter than your average bear.
If she just wants to be another talking head, there's nothing really wrong with that, that's operating on a completely different level from actually being in the fight.
As for the GOP-E having her in their sights, do you really think there ever be a time when that won't be true?