Apollo has officially been released on labs. Included on the labs site is an introductory article I wrote for working with the File API.
Check out the plethora of information available for budding Apollo developers on the documentation portion of the wiki. The documentation features quick starts, in depth guides, tutorials for common operations, etc. There's a lot of good stuff in there, so prepare yourself for possible information overload.
It's an exciting time to be a Flex developer. I'm personally looking forward to the opportunities that Apollo brings to the table. There are a few open source Apollo apps up my sleeve that I plan on releasing in the coming weeks and months. The first one, of course, being FVNC-related.