A single merger can represent days, months, or even years of work. Most of the commits are relatively small, but once in a while you get absolutely huge changes like Tev_Fixes_New or the GLSL rewrite that span across years between initial concept and merged code. There's a special sense of accomplishment when one of the long awaited changes finally show up in the emulator. The number of commits and the amount of code changed; neither of those indicators often tell of the trials faced by the contributor over the course of their journey.
And don't think that just because the code is merged that things are finished. Part of the purpose of having progress report is to put a spotlight on some of the latest and greatest changes. The users are the last line of defense against potential bugs, problems, and unintended consequences that often come with new features.
All of the latest features mentioned this month can be found in the latest development builds available here.