If you are a marketer and you aren't trying to use Facebook in some way, you're like a professional athlete not spending any time in the gym.
C'mon, that's not true. Would you say the same about AdWords or any number of other marketing channels? There are tons of business models that don't rely on and/or would benefit very minimally from Facebook.
I'm the first to admit these social sites present a lot of opportunity (as I did in my OP) but they certainly aren't needed or important in a lot of cases and I'm surprised by your blanket statement about Facebook.
Without all of these social sites you are hoping and praying that the SEs bring you free traffic. These are new ways to bring free traffic in.
Not sure if serious here. Surely you aren't suggesting that social sites and search engines are the only ways to get traffic LOL. I get hundreds of thousands of visitors a day to my sites and don't use either.
Free traffic? Free traffic is nice and all, but most serious businesses have advertising budgets and don't rely on free traffic. It's great that things can "go viral" a lot easier these days with all the social sites, but I know dozens of people who have made millions online and only 1 of them did it with "free traffic" (and this was a few years ago before the social site craze).