My thoughts? Only absolute weirdos would have sex with family members.

Damn... why couldn't it be Austria.. then we could have made jokes about Rollstopable ...

Hmm, is 2 cousins having sex considered incest? (Catholics can marry their first cousins, right?)

Mostly, no, it's not considered incest. In some places in the US it's illegal but marrying a first cousin is legal in almost all of Europe. I'm  not sure what the Catholic church's stance is on the subject, though.

Aha, anyways, incest should be legal between consenting adults. And so should adultery (it's illegal in my country).

Morally I couldn't care less - genetically it's bad news so I'd actually object on those grounds: bad for the species.

I guess you could say there are two major types of families. There are the loving families and there are the unloving families. Suddenly I feel a lot happier about being raised with the latter than the former.

Nothing wrong with it, as long as both are old enough. That is, as long as it stays on 'fun' level instead of something too serious. Really, only inbreeding should be restricted.

Yep.  Though it gets iffy if it's say a 16-18 year old child and a parent as you could claim their parents itentionally socialized them to act that way.

Doesn't it take like... dozens of generations of inbreeding to show effects?

The only real issue is genetic diseases becuase your basically guranteeing it will strike.