Essentially this question is suggesting that the stereotypical heterosexual roles should also apply to homosexual relationships. And I don't think this is really where we want to be heading... Clearly the heterosexual community has destroyed the 'institution' of marriage with a divorce rate of approximately 40-50% for first time marriages and 60-67% for second time marriages, where 25% of women have experienced domestic abuse, 3/4 of all Americans know someone personally who has been a victim of domestic violence, and not even to mention the unfair marital roles where one person (typically the female in heterosexual relationships) is responsible for not only pulling in their share of the income, but also taking care of the children (possibly parents as well) and the household.
With new laws allowing the marriage of homosexual couples, I think we should see this as an opportunity to change these imbalanced, unfair, traditional roles. Each individual in the relationship should have an equal stake in the relationship!
So to answer your question, as most everyone else has said, if one of the individuals desires to change their name, they may, but neither should be forced (and clearly no one is being forced) to give up a part of their identity in exchange for their partner's. Personally, though I have a love-hate relationship with my name (as I'd imagine most people do to some extent), I can't possibly see myself, in any situation, giving up something as closely tied to my identity as my name is for someone else.
(Maybe I did blow this question a bit out of proportion, but I'm young, and everything's still a cause for me.
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