Kye said:We have been trying to get SA-MP listed in Xfire since 2006, and have given them the details to do so. They have said that it's not possible to properly detect mods like SA-MP, although now the have listed Multi-Theft-Auto. 90% of the screenshots and videos of San Andreas shown are from SA-MP.
Even if you don't use XFire, please do vote for us in this thread on their forums:
http://www.xfire.com/xf/modules.php?name=Forums&file=viewtopic&t=218924