Starting to hit bumps with xorg-x11, I'll wire this one to depend on them. If you don't care for this, just close it "INVALID"; otherwise, I'm going to link this to all the bugs I report that involve switching from xfree to xorg-x11 (not bugs related to xorg, just bugs related to switching). I'm big on organization.
Rather make it a switch from x11-base/xfree to virtual/x11 as discussed in #44864. Also as mentioned there, a list of packages attached to this bug that depend on x11-base/xfree (or really mention it at all, to ensure no ebuild hacking breaks) would be useful.
Switching from x11-base/xfree to virtual/x11 as discussed in bug #44864 would be something that would be a part of this, and thus that this bug would depend on. This is more of the big "to-do" list as gentoo gets switched over.
That's all of 'em.