Mine is pretty messy, it's got plants in pots on it shedding leaves and so on. I clean it pretty rarely. If there are germs on it, they're my germs anyway, right?
Here's another interesting stat: apparently, the average N. American kitchen sink has more fecal bacteria than the average N. American toilet bowl. The reason is the amount of meat we tend to eat - the animals' intestines rupture and spill feces on the meat during the butchering process something like one in five times. Then we trim the fat from a cut of meat and toss it in the sink, etc.
Sorry, no links; it was in the Globe and Mail a month or so ago.