I know this will be somewhat partisan, but if you go to this link for the new campaign ad http://www.johnmccain.com/Informing/News/PressReleases/53253e8c-8a7e-42c4-9918-3b00f9e1daa7.htm , and go to about the middle, there are press summaries on this very issue.
I believe that they are cognizant of the issue and are waiting for the right time to pounce on the Obama/Biden campaign. Perhaps during the interview with ABC, but during the debate for sure.
I think during her spending time with Gibson, Palin will talk about the issue in details.