This makes my green heart happy. Above is a video of the Einstein Newton emulator running on an iPhone 4. Newton OS lives! ... Well, sort of.
You'll notice that it's kind of slow for now, though the project's developers say speed will improve. Still, it's a full Newton, with hand writing recognition and everything. They also intend to get it working on the iPod touch and iPad. If you want to get your hands on things right now, the source code is available here. Developer Matthias Melcher says he's going to submit the emulator to the App Store, but he's not holding his breath.
Congratulations to Matthias for the successful port, Paul Guyot for writing the emulator in the first place (and keeping it open source), and everyone who contributed to the project. I hope to have this on my own iPhone 4 soon.