In the late 80s and early 90s, GSS participants were asked if they have ever served in the military. Slightly more than 20 percent of gay men (of all ages) said they had. This is a much greater estimate than we would get for young gay men now, but let's stick with it. According to CNN, only one-sixth of gay enlisted men plan to come out now that the "don't ask, don't tell" policy will be ended. So multiplying the two percentages gives us 3 percent of gay men who will ever make use of the new policy. According to research, around 3 percent of all men are gay, so if we multiply 3 percent by 3 percent, we get basically 1 out of 1,000 men who will ever be affected by the change in policy. The number would be probably be even smaller for women since there are half as many lesbians as gay men (according to the GSS, 21.6% of lesbians say they have served).
I'm pleased that the Democrats feel so good about themselves after getting the policy changed, because otherwise it kinda seems like a waste of time.
Personally, I wish lawmakers would focus on issues slightly more important; for instance, whether the hundreds of thousands of embryos and fetuses that are killed every year are immature humans or not.