When and where does Panels get the title out of a View?
I was hoping that someone would answer this, so I wouldn't have to answer my own question when I found the solution.

Credit goes to a co-worker (who doesn't really post here) who reminded me that you also need to update the handler:

function foo_views_pre_view (&amp;$view, &amp;$display_id, &amp;$args)
{
  $view-&gt;display[$view-&gt;current_display]-&gt;display_options["title"] =
  $view-&gt;display[$view-&gt;current_display]-&gt;handler-&gt;options["title"] = "Foo";
}


When you do this, the title does propagate properly to the pane title.