xbmc automagically links against libbluetooth.so.3. There is no configure option or use flag. It will link against libbluetooth if bluez is installed. xbmc should depend on at least net-wireless/bluez-4.98-r2 because of bug #403341.
Created attachment 301905 [details] emerge --info
Created attachment 301907 [details] ldd /usr/lib/xbmc/xbmc.bin
should be all set now in the tree; thanks for the report! Commit message: Control bluez dep with USE=bluetooth http://sources.gentoo.org/media-tv/xbmc/xbmc-11.0_beta3.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/media-tv/xbmc/xbmc-9999.ebuild?r1=1.100&r2=1.101