Sex has been about much more than reproduction in human society for a very long time. And it's about more than reproduction in other species as well. [link|http://en.wikipedia.org/wiki/Bonobo|Bonobos].
And the way things are going, [link|http://www.newscientist.com/channel/sex/mg19225741.200-reproduction-revolution-the-conceivable-future.html|sex will not be about reproduction] (at least in Western societies) too much longer.
The simple truth, is nobody will remember us in 100 years. That's true, but it's not the whole story. ;-)
Cheers,
Scott.