If you don't do much with images it's probably not anything you need to worry about. If you care about things like HDR, it means you can now use PNGs for that. If you work with graphics for a living, it's probably a good idea to learn what's changed in the standard.

PNG was a huge deal when it was new, mostly because of all the headaches Unisys was giving everyone over GIF compression patents. This new standard is mostly of interest to people that have reason to care about what format their image data is in.