Color me clueless

Can anyone explain to me in non-obscene terms what gays mean when they refer to “teabagging?”  At Power Line, Scott has noticed that more and more CNN and MSNBC employees and talking heads have been making chortling references to teabagging.  I knew about the chortling references, but thought they simply were snarky comments about how silly tea bags are as a political weapon.  Apparently, though, there’s a larger subtext.

Read the Power Line post if you will, and then please get back to me with a politely phrased (clinical or euphemistic) explanation about what’s going on here.