$summary pretty much says it all. upstream moved from using /media to /run/media.
ah, this is actually not an issue since udisks2 will create the entire directory structure on it's own if it's missing as per g_mkdir() in src/udiskslinuxfilesystem.c
...if we're reading the same code, it looks as if only /run/media and below were created, not /run itself.
ah, sorry.
Fixed by: http://sources.gentoo.org/viewvc.cgi/gentoo-x86/sys-fs/udisks/udisks-1.97.0.ebuild?r1=1.2&r2=1.3