Studies have shown that children being raised by gay couples may be better adjusted and capable than those raised by straight couples. For one thing they don't have various gender roles (often conflicting) being forced on them. By roles I mean stereotypically masculine or feminine traits/tasks.

Of course I also saw a study that showed the children raised by gays were more likely to be involved in backlashes against that culture because of treatment they received outside the home growing up...I guess you'll always find what you're looking for with regards to studies (depending on who funds/supports them).

Most of the family values that we take for the "norm" don't exist, they were a creation of the post WWII period that enabled all the returning men to enter the workplace again (displacing all the women that were quite happy to hold those jobs while they were gone...). Basically what we all take as the model family does not exist except in 10% of households and the dynamic is changing rapidly.