Just out of curiosity KC, is your brother gay/non straight also? The reason I ask is because a big part of my psychology course I took was, of course, twin studies, and there were many examples of twins being closely related in sexual preferences (ie, both being gay, both having identical taste in women, etc.) This is of course assuming that you are identical, not fraternal twins.
One interesting case study we looked at, involved identical twin boys, Jim Springer and Jim Lewis, whom were separated at birth. Despite having been both raised in separate adoptive families, they discovered after meeting for the first time at age 39 they had an obscene amount in common. To quote my textbook,
Quite similar indeed!
At any rate, I wish I had a twin, I think it would be interesting to see how similar (or different) we turned out from each other.