1. The symbolism was a bit heavy-handed. It's frustrating that Mad Men creator Matthew Weiner doesn't trust viewers of the show enough to allow symbolism to live in an episode as suggestion and not insistence. The Mad Men audience is small and self-selecting; it is made up of people who choose to watch a show that requires attention and rewards patience. These are viewers who would have gotten the effect, for instance, of Don lying in bed looking precisely like a dead body in a casket, even if his wife had not, a moment later, swept her hand down his face to close his eyes.
In a case like that, the introduction of a reference — here, a reference to Don as a dead body — feels like art, while the second feels like annotation. Similarly, a writer as creative as Weiner surely could have avoided the Roger Sterling monologue that explained the theme of the episode (and perhaps the season) explicitly before viewers had a chance to see it emerge organically from the story. While the sense of death hanging over the episode was interesting, it would have felt more eerie and encroaching if it hadn't felt quite so forced.
2. The hair means everything. How monumental it felt when Betty dyed her hair says a lot about the coding of characters. The same thing happened when the classically gorgeous January Jones first wound up in a fat suit last season; her current padding seems less extreme and is more flattering, and they're not being quite so brutal to her face. Betty would still see herself as a loyal housewife, just as she did when the show started, but the visual coding of her character — cheery floral dresses, tiny waist, icy blonde hair — has gradually been breaking apart. (And depending on how much you believe in the meaningful power of the homophone, take note that both Don and Betty are exploring the meaning of dying/dyeing.
Many of the other characters are changing their looks for reasons of shifting fashion (most catastrophically, Harry Crane) or age (Pete Campbell's poor hairline), but Betty's appearance is changing for reasons that seem specific to her character. Interestingly, the hair also gave her a visual echo with Megan just moments before we learned that Megan's life is echoing Betty's in ways Megan is not aware of.
3. Patience is a virtue. For a two-hour episode, very little actually happened in terms of plot. Betty unsuccessfully searched for a character we really don't know and wound up lecturing (and being lectured by) a bunch of hippies, Don blew a pitch because he couldn't stop accidentally hammering the death metaphor, Peggy handled a crisis at work, and Roger's mother, whom we didn't really know, died offscreen.
But that's the way premieres of Mad Men often go. Last season's premiere was dominated by Megan's performance of "Zou Bisou Bisou," not by anything earth-shattering. Weiner uses premieres to place characters very specifically; to re-anchor the show to the historical moment at which it is occurring. Not every show benefits from a full evaluative exercise of every episode, and this is one where experience has taught me not to be surprised or discouraged if the first episode of any given season doesn't set my soul on fire with excitement.
4. Peggy is the greatest. Elisabeth Moss is giving my favorite performance on television, I think. Peggy is so deeply and richly written that she has a huge head start, but Moss is so funny and nuanced in her choices that she's utterly sold the transformation of Peggy from a young girl who desperately wanted Don's approval and would (GET THIS) fall for the charms of freaking Pete Campbell to the utterly self-possessed person she generally appears to be now.
Obviously, she still has her vulnerabilities, but Peggy has carried most of the weight in Mad Men's examination of the changes in roles for women that fascinate Weiner so much, and Moss has been asked to do a lot. A lot. And she's done it well. Her late-night phone call with her buddy Stan was the most endearing person-to-person moment of the entire episode, and as Don struggles to not think about death all the time and continues to be unable to navigate a single human relationship successfully, it seems that the student has pretty clearly surpassed the teacher.
5. ...Still no. As interested as Weiner is in issues of gender, he doesn't seem to have any interest in issues of race, and the premiere showed no signs of that changing. Other than Don's secretary, people of color (and everything they might be doing outside the walls of the building) continue to be mostly invisible, which seems more than anything like a missed opportunity for a show that's now at the end of 1967. But for more about this, I would refer you over to NPR's new blog Code Switch, which you should be getting to know anyway, and where blog host Gene Demby has just written some very smart words about this very thing.