I've said before that there is probably an interesting alternate universe out there was G+ was built on top of Talk, Reader, and Wave instead of replacing those three. They really did throw out several babies in trying to throw out their over-silo-ed bathwater. One can only imagine the world in which the UX work applied to the G+ walled garden Facebook clone effort had instead been used to polish (a federation-capable) Wave and make it a consumer friendly product...