Did Don Really Find the Right Woman?

(SPOILER ALERT if you haven't seen the finale.) Mad Men fans issued a collective gasp around the midpoint of last night's season finale, when Don Draper proposed to his secretary, Megan. On its face, this is Don at his worst, taking the easy and exciting over the complex and substantial (poor Faye) and hastening his descent to Roger Sterling's level of buffoonish irrelevance. But with time, some of the decision's merits emerge: She's great with his kids (which Faye is not), smart, self-confident, and does actually seem to care for him. So what do you think: Has Don finally found The One, or was Faye correct to warn, "I hope she knows you only like the beginnings of things"?