RussianiPhone.ru claims that they have seen iPhone 2.2.1 Beta 1 and that it implements Push notifications as well as over-the-air MobileMe syncing with Notes support.
As proof they've posted a screenshot showing the Notes and Calendar applications with a update badges displayed (though this is relatively easy to fake).
MacRumors can't verify these claims at this time. Apple has not yet seeded iPhone 2.2.1 Beta 1 to developers, so if RussianiPhone.ru does have a copy, they obtained it outside of any public distribution.
While Apple originally promised Push notification support for September, Steve Jobs acknowledged a delay in an email and said they wanted to "get it 100% right the first time." Developers and users have been anxiously awaiting the release this new feature. In the current iPhone firmware, applications are not allowed to run any background tasks. As a result, an application like a Instant Messaging application would be unable to notify the user that a new message had arrived. Push notifications would provide the tools to trigger these alerts.
Update This is fake.