Why ignore her when one can ridicule her, ironsides? She provides plenty of fodder for comedy, like Dan Quayle did. Indeed, before the election, I expressed the wish, I almost wished that McCain/Palin get elected. Imagine how much material that would have given comics (or indeed to everybody) with Sarah Palin in the news day after day. Dan Quayle would have paled in comparison.
As to her supporting whoever the Republican nominee is, that depends upon who the nominee is.
It was clear from the New York Congressional election that Tea Party supporters and Palin will not support a Republican candidate if he doesn't not come from the far right.
So if Republicans nominate somebody like Huckabee, I see Palin supporting him. If they nominate Romney, forget it. There is no way Tea Party and Palin will support him unless he moves sharply to the right (and then he may have problems with the electorate at large).
If they nominate Huckabee or Romney forget it. They have to find someone new or anyone who will get away from the abortion issue. They run on that and it will be another loss. Sarah will support whoever they pick or this will be her last hurrah.