Do you believe that the government has the right to tell people who they can or can't marry?
Prop 8's the one thing that harshes my buzz about finally having a President that talks like a grownup adult (that, and the fact the Three Stooges remain in power here in Florida: I guess running Joe Garcia, a charismaless nerd technocrat, wasn't enough). Proposition Eight is an example of the ugly Karl Rove "old" school of politics the American people categorically rejected: divide the electorate with an issue and hope you end up with the bigger piece. Usually, it nearly always involves smearing a minority group (undocumented workers, homos, Ay-rabs).
This actually affects someone close to me personally, because my Mother has a "civil union" with her boyfriend that gives her hospital and visitation rights and allows them to share insurance.
Incidentally, I fully expect a lot of comments that go "Hey, if you're so tolerant, how come you're not tolerant of my intolerance?" Those just crack me up.