With Liebling, we started discussing names about 4-5 months before conception. We're currently discussing names for Stormy, although not in a very focussed way, just in a "that's a nice name" sort of way.

Having said that, with Liebs we had the boy name picked at about 12w, but post-dates still didn't have the girl name picked. So it's a good thing we're starting very, very early with Stormy!