The criticism I have heard is that she may have fired someone because he wouldn't fire her sister's ex. I've heard that she originally supported the Alaskan "bridge to nowhere", although McCain specifically criticized the funding for it. I've heard that she and/or her husband have been involved in a political party that calls for Alaska's secession from the Union.
Those are areas of way more concern than her daughter's pregnancy.
Way more important SB. There's also her quote that by being in the the Iraq war the U.S. is doing "God's will."