Apple today seeded a new round of betas for its next minor updates to developers today, including iOS 10.1, watchOS 3.1, and tvOS 10.0.1. You'll notice that macOS 10.12.1 Sierra is missing from that list, but that's only because its beta was released yesterday. In fact, that was the third macOS beta in less than two weeks.
Today's builds are all the second Developer Betas for each of their respective operating systems, showing up 13 days after the first. They're only available for developers right now, so if you're on the iOS Public Beta, be on the lookout for it tomorrow. Of course, there is no Public Beta program for watchOS or tvOS.
The main feature in the new update is Portrait Mode for the iPhone 7 Plus. It allows for the user to take a photo that has bokeh, a blurred effect in the background. The feature is still in beta, of course, and it doesn't work that great yet.
iOS 10.1 beta 2 fixes an issue that causes Notes to crash, while the new watchOS build fixes WatchKit issues. As you can see from the version number, tvOS 10.0.1 is a bug fix update, and that's exactly what the release notes say.