I last looked in the hive a week ago. It's best not to disturb bees too much if you can help it, especially when they're newly installed. I took it as an encouraging sign that they were a little more spread out than last time (when it was cold, admittedly).
Even better, the window revealed that they are indeed building comb. I would guess they're up to seven or eight bars now. (You can click the photo below to make it larger.)
It looks like they are following the wedges, from what I can see. Maybe next week I will do a real inspection. I'm a little trepidatious about doing that, partly because I'm worried about freaking out the neighbors, should they see me through the fence.