Nope, there is no doc at 10. There is a NIM number out to create one. Perhaps use Module Docs to find direct info for arcpy through pydoc. Hopefully, it will be here by 10.1
I have found the online help for arcpy very useful. I guess I'm just used to staring at a Model diagram!! I just need to get in and get my hands dirty now.
I agree, a model will be very useful for arcpy, figuring this is a major enhancement to the esri python at 10, and more updates will be coming at each new iteration. Help has improved a 100% at 10.