After a lengthy wait between releases, a new version of MAME is out. While I did not see any updates related specifically to our CoCo (or cousins) I can see there are many updates to MAME itself. You can read more about that here: https://www.mamedev.org/
When updating your CoCo-Pi, please make sure to select “Update CoCo-Pi from git repo” and “Run CoCo-Pi fix script” in order for all the changes to be applied. Install the latest MAME package (from the same menu). Select mame-0.253-1 as the default version.