Sounds like they were showing how foolish the MSM has become over Palin and mocking them for it.
They could have picked a different topic as an example.
Call me overly sensitive but I find nothing funny about incest, having gone through it myself from age 8-15 I can tell you, it's not funny at all.
Someone might call you overly sensitive except for the fact of your personal experience, which certainly makes your reaction understandable. Bottom line, it appears to have been yet another completely tasteless piece of television, albeit aimed in the right direction (at MSM bias). One reason at our house we avoid TV like the plague vector it is. But for those already infected with this plague of tastelessness, maybe (hopefully) even this crass bit provided a gleam of enlightenment.
I'm very sorry for your experience, and for others who have been through anything similar. May God grant you a special measure of His grace, strength, and comfort.