Well, they're raving over on Capo's board about this show's 3rd season possibly ranking as one of the top 5 television seasons of all time, and it's pretty apparent that this show has done something really special. The audience has been waiting for the Kennedy assassination for about the past year. It kept drawing closer and closer, but producers gave no indication of when it would occur. We didn't know when it would happen, only that when it did, the show's narrative, along with the country at the time, would likely be affected greatly.
I won't give away that event for those who haven't seen it, but as for the season 3 finale, it definitely marked a complete 180 turn in the show's narrative, and we can only assume that season 4 will have an entirely new set and markedly reduced cast when next year's show begins. Since the audience will see the previews for season 4 and have an idea of how things have changed drastically, I won't worry about spoiling the ending of 3:
Don learns from Conrad Hilton that Sterling Cooper is to be sold yet once again, and because of this pending corporatization, former owners Roger Sterling and Burt Cooper, along with lead protagonist Don Draper, orchestrate their own terminations from the company in order to detach themselves and form the new firm of "Sterling Cooper, Draper and Price". The 'corporate-cout' does not preclude the existence of "Sterling Cooper", haha, but I assume they'd change their name. The three protagonists of the 'conspiracy' (with the assistance of British corporate liason, "Price") decide to take with them Peggy, Pete Campbell (who, last season, appeared to be the nefarious villian pitted against Don), and two other staff members who are crucial to the new firm's birth. Time was of the essence with the move, which included the 'acquisition' of certain production and art materials pertinent to their accounts, all occurring over the weekend during the middle of the night.
Because Roger Sterling still had 1 year on his contract with 'Sterling-Cooper,' combined with Draper's 3, in order to take Sterling's 24 million dollar American Tobacco account elsewhere, the three decide to arrange their dismissal from the firm through the efforts of soon-to-be displaced British liason, Price. It was all a great exercise in early dog-eat-dog capitalism and corporate takeover and counter takeover.
Concerning the Draper's marriage: From what I understand, the real life ad-man split from his wife (children?) and later married a member of his staff, whom he spent the rest of his life with. Thus, I think what we've seen with Betty and Don is final. The audience has had an eye on he and Peggy since the start, and his emotional plea to her to join the new firm after he and Betty's split was one of the pinnacle moments of the show, as well as their relationship. As expected, Peggy's character has experienced the most growth.
Don to Roger (on their way out): 'I never pictured myself working in a place like this'. Biggest understatement of the show ... And each episode always closes with a fitting song to accompany the plot--much like David Chase did w/ The Sopranos--one that's accurate to the show's time period. This really was such a tidy little ending in spite of the mammoth movements in the story arc, etc., and this Roy Orbison number 'Shahdaroba' was the perfect way to end the season:
"When your dreams die and your heart cries, Fate knows what's best for you Face the future and forget about the past, In the future you will find a love that lasts"
