First, that Professor Gates is the only one whom I'd even consider trusting to pick up a sixpack on his way over for a backyard cookout. He had a Sam Adams Light. I'm not a huge Sam Adams fan, but it's a solid beer ... it works.
Sgt. Crowley went all fru-fru, ordering a Blue Moon. Good basic instinct (it's a wheat beer), bad pick (it's a Coors/Molson product and it's flavored with orange peel and usually, including this time, served with an orange slice). For the love of all that's holy, man, if you want a wheat beer, go with a hefeweisen, not a witbier: Boulevard if you can get it, Widmer Brothers or Paulaner if you can't.
Leave it to Joe Biden to go to a beer summit and not have beer. He had a German beer substitute, Buckler, made by Heineken. Sort of like going to a wine tasting and asking for a cup of vinegar.
As for the president ... wtf? Surely the leader of the free world, messiah of the Democratic Party, ayatollah of rock and rollah, etc., etc., can find something better than Bud Lite in the White House fridge. God help us all if he decides we need a national beer care plan. And I'd feel much better knowing he's got control of that nuclear football thingum if he'd ordered, say, a Fat Tire.
Obama was correct in pointing out that this wasn't really a summit. Beer and pretzels do not a summit make. For a summit, you need Kentucky bourbon and barbecue.
[Source for the participants' beer -- and non-beer -- libation orders: New York Times]