Here's the calculus on Sarah Palin's decision to resign -- and it's elementary:
1. Don't resign
a. Bankrupt family defending self from bogus ethics allegations
b. Accomplish nothing as governor since Democrats have vested interest in blocking any progress
c. Remain butt of every liberal pundit/comic/feminist with constraints of public services preventiving effective means to fight back
d. Fail to influence national policy at a critical time due to pressures of office and Alaska's geographical remoteness
e. Be in poor position for 2012/2016 Presidential race because of the above
a. Give Lt Governor chance to use incumbency for 2010 election
b. Let Alaska move forward by removing Democrat incentive to block progress
c. Make family financially secure through speaking fees, books and punditry
d. Use media platform to advance policies that matter personally, develop reputation for deep understanding of national-level issues (economic, foreign policy), and use media platform to go on the offensive against opponents and enemies
e. Play 2012 kingmaker role by consolidating and delivering GOP base, speaking and raising money for candidates ("Mitt, let's make a deal.")
f. Use kingmaker role in 2012/2016/2020 to win prominent, substantive national role (VP, Energy Secretary), establishing a national-level track record and creating an option for Presidential run in 2016/2020/2024 while still in political prime
g. If (f) doesn't work out, enjoy being the next Rush Limbaugh -- after all, living well is the best revenge.
For most, candidates, public office is the logistical base from which they operate.
By giving up the Alaska governorship, Palin has no public office base for her opponents/enemies to attack.
Many might deride Palin, but no one should underestimate her.