MacRumors reports that Apple today seeded the fourth beta of OS X El Capitan to public beta testers

The fourth public beta follows the launch of the sixth OS X El Capitan developer beta, which was seeded to developers yesterday. Aside from new wallpaper, no outward-facing changes were introduced with beta six, suggesting it's largely an under-the-hood update with bug fixes and performance improvements.

  Apple Seeds Fourth OS X El Capitan Beta to Public Beta Testers