I was eagerly awaiting someone to take this to viral video task, and now here indeed is an extensive scene by scene comparison of Julianne Moore as Sarah Palin in "Game Change," and Palin herself.  It makes clear how masterful Moore's depiction was -- which I thought fell far from simply impersonation (even if the film that surrounded the performance was somewhat less admirable).

Take a look, though perhaps wait until after you've seen "Game Change" if you'd like it all in one context -- even if you've seen it all before anyway: