It may have passed many by (it certainly did us), but Google has reinstated the pink boundary and shading around town searches, as below.
Why is this important for local SEO? Put simply, if your ‘Google My business’ location is in the shaded area and boundary, you’re classed as being in Burton on Trent by google and are more likely to show up on the local pack (map search listings). If you’re outside of the shaded area and hoping to show up in the local pack, you may struggle. Nothing has changed of course in that respect, but google is again showing us the boundaries for the towns when you do a search for the respective town.