The Clintons were always big on "triangulation", trying to corner both the Left and the Right. Probably because of how they came out of Arkansas politics, where there was a strong southern social conservative streak which trended right, but lots of poverty, which pushes left, and packaging it up in the fading tradition of the Southern Democrats, but without the racial component to it.
In practice they were careful to be talking a good centrist/moderate game, but unlike most Democrats/Libs who all give that lip-service, their strategy also included actually being wise enough to throw in a few conservative tidbits, like going along with welfare reform, hoping it would make the more progressive bits of their policy, like tax hikes and socialized medicine more palatable. The other component was the Clintons CONSTANTLY had a wet finger in the wind to see which way it was blowing.
And Clinton's kind words for Palin is just more of that. And because of the relative peace and prosperity of the 90's, Clinton is doing minor positioning to see if he can get his administration and Hillary associated with the 'good old days', hoping a return to those good times can be linked to the Tea Party's grievances now.