I finally saw this. I didn't gain much by it. Most of the salacious details have already been widely available so it played more like a "Sarah Palin's greatest hits, SNL version". I will note instead that a lot of media coverage focused on whether it was a sympathetic portrayal (or not) of Palin. And I would say "yes" to both.
For about the first 20 minutes or so, we who have so generally despised this woman and her politics and dearth of grasp for policy, were treated to a relatively humanizing depiction. What I described it as was taking a regular person and telling them that they were to perform an Olympic class figure skating routine with maybe a few weeks to train. The fact that they would be able to skate and only fall down a few times when trying to jump or twirl might be viewed as a major success. What we saw was a small town mayor, small state governor shoved into the national spotlight. And her subsequent inability to grasp, at first, how big of a stage she was now required to be on (hence a bizarre fixation on her reputation in Alaska). And despite my thorough misgivings, I have to admit she had a handful of political successes (her convention speech was complete with offensive but effective red meat for example, rallying the tepid conservative base behind McCain), as even the most novice poker player can win a hand or two. For that part of the story, it seemed like a Mr Smith goes to Washington element. Armed with only the most tenuous grasp of what role was to be played the role goes about as well as you would expect, and while I don't have much sympathy for that, the fact that I'm aware of how little voters themselves know (and she expresses this herself), does much to alleviate my disdain. Indeed, some of the attacks she received should be rightly viewed as ridiculous in retrospect (the Trig story in particular, but also the clothes shopping bill, etc, some like the newspaper reading story, the Russia from my house, and a few others are perfectly legit)
After the Biden/O'Biden gaffe however, it stops with the humanizing and becomes only the story of the now terrible public figure "we" are already more familiar with, who doesn't prepare, uses a shotgun method of speaking to "reason", and demands attention rather than earns it. It ceases being a story about her and becomes a character story where she is now the villain for all involved. And to some extent, deservedly so. There can be no sympathy for the sudden transformation into the campaign diva achieved when the campaign sort of figures out how to aim her inability to make cogent points to reporters by using her as attack dog for stump speaking. But it's also a very messy transition that doesn't really show the tragic flaw in the downfall story well. Bush and Cheney both expressed serious reservations about her political acumen and experience, and say what you will about the terrible political positions of those two as public figures, they were at least successful politicians with a grasp of politics. It's not made expressly clear that it is, in fact, almost her inability to grasp politics and policy especially that allows her rise, and largely explains her fall. Someone who wanted to fight in a state that McCain lost by 17 points is a child politically and has clearly no idea what she's doing. But she was elevated to a position of importance and a spoiled child, naturally, has temper tantrums. That seems to be about what the story should have been, but wasn't.
What they didn't really explain is how her selection cost McCain a few votes among independents and swing voters, and hence a few points in the national elections and perhaps a couple states (plus some congressional seats that they were able to recover in the off year election). It was, probably, a foregone conclusion that Republicans were going to lose that '08 election, but the margin (of 7), and the popular vote being over/under 50% was something they could have used politically and wouldn't have required obstinate refusals to govern at the national level as a result. Palin revealed a great sea of ugliness that liberals and Democrats already suspected was there because of the Bush-Cheney years and that independents were able to see plainly with their eyes removed from the scare mongering of Iraq-terrorism links that dominated the '04 campaign.
The move to the right and the rhetorical nonsense and missing grasp with even the most inescapable facts and figures that Palin represents is also likely an ongoing story and problem for conservatives/Republicans. I suppose they hinted at this through the ugliness of that campaign and the vigor with which people embraced her, and by extension, hated her opponents and critics. Fortunately, Palin herself has largely become irrelevant to that story. I don't think we can say that she started that chapter of history and thus the trendline in hindsight, but she may have magnified its importance. I also don't think this was a very sympathetic portrayal of her place in that history, it largely Tina Fey'd her. But I'm not as likely as some to care.