I think the age thing - especially moving forward - is geographic.
When I go out with my friends I'm approached by more young white guys than any other group. After that comes young black men. (YBM are by far the most vocal - they will make comments or *ahem* YELL at you from across the room in an effort to get my attn.) Older WM tend to approach me when I'm minding my own business - I got invited to a corporate christmas party while pumping gas
If it's a Older man in the club - a lot of the time he's foreign. I have NO idea what that is about.
erplexed
In college I found that young white men are interested, but sober many of them are afraid to approach black women b/c they assume that we don't date "out". I've literally heard them say this. It's kind of like some BW don't check from them b/c they figure they aren't checking for us, and some WM don't check for us, b/c they figure we aren't checking for them.
Now..you get some liquor in 'em and it's a whole other story.