The is another .NET object persistence framework out there called Gentle.NET.
It works with all the usual .NET supported databases like MS SQL Server, Oracle, PostgreSQL (using the NPgSql provider included with Mono) and MySQL (using the ByteFX data provider) and MS Access.
What is really nice about this framework is that it defines a set of .NET "attributes" that you use to decorate your objects that you want to be persistable by the framework.
So no syncing XML config files with your objects in order to make them persistable.
You definitely gotta love .NET attributes, and hopefully JSR-175 will make the Java developer's life just as convenient.