I know that as a baseball fan, I'm supposed to be rooting for a Cubs/Sox series, but believe it or not, I'm not. It's just too much, too perfect. It's like having a cheese steak with cheese fries and a pie ala mode for desert. It's like it being 1973 and seeing a Stones/Who double-bill. It's like what would have happened if the first two movies of the Star Wars prequel would have been really, really good.
A Sox/Cubs series would be like that.

Besides, it's a part of baseball that the Cubs and the Sox always lose. It's part of the fabric, the mythos of the sport. The Cubs are the loveable losers and the Sox are the heartbreaking tragedy. If both of them get in, that means one of them has to win and then all of a sudden, the very nature of baseball changes. Would Charlie Brown be Charlie Brown if he won a few times? Would Keith Richards be Keith Richards if he sobered up? Would "The Real World" be "The Real World" if they actually brought in a bunch of normal, non-fame whore types? Nope. And that's what it would be like if the Sox or Cubs win it all. Besides, it's much more enjoyable watching the Sox come incredibly close only to lose in tragically heart-breaking fashion. Nobody's more entertaining than angst-filled Sox fans.

PS- if David Stern were the Commissioner of baseball, we all know it would be a Cubs/Sox series. Just a crucially timed foul-call here or there and viola.