iPhone OS 4.0 Beta 2 slipped into the iPhone Dev Center earlier, but unless you're a developer and really need to test apps, it's best to skip this extra buggy beta and just keep playing around with the first.
I realize that you're curious—after all iPhone OS 4.0 Beta 1 was full of new features—but Beta 2 is a bit of a letdown. Aside from the annoying inability to take screenshots, Beta 2 actually left me struggling to do simple things—like using the Camera app.
For whatever reason, the Camera app freezes and doesn't save pictures, the on-screen keyboard refuses to pop up when I want to add my email account to the phone, and third-party apps go nuts.
Yes, this is all expected with a beta build, but many of us are prone to putting such things on our devices for the sake of trying them out and discovering new features. When it comes to iPhone OS 4.0 Beta 2 though, skip that step unless you have to and just keep playing with the first beta.
Or let us risk our iPhones—and patience—to find the new features for you and leave your iPhone happy with a public OS build.