This isn’t an update to the base OS software, it just bumps the firmware to 02540.00019.1523x.4500x- presumably in preparation for Windows 10 mobile.
No other devices received updates at this time as far as we know. You can download the update by going to the phone update option in settings and tapping press for update. Remember to place your phone on a charger as a precautionary measure in case the battery dies during the update.
Facebook today released a new update for its new Windows 10 app. This update is a minor and mainly brings along bug fixes, particularly to contact sync.