Is this a sign that Microsoft are seeing the value in Android? Already having released an official Hotmail app, they have now released OneNote Mobile.
To use the application you will need a Windows Live ID and Password however these are free and relatively pain free to set up too.
Microsoft already make quite a bit of money from Android through forced licensing deals and with OneNote on Android it looks like they could make more given that you are allowed 500 Notes for free before having to upgrade the app via in-app purchasing.
Download: Microsoft OneNote