If you like to see a few of the new things we added for lion, you can take a look on the documentation. Those items will be documented and tested in the next days.
We are working on an update to the StoreKit classes to get them up and running. Testers welcome.
And finally we recommend to update to latest plugins if you plan to support Mac OS X 10.7. There is so much we fixed over the last weeks to get compatible: for example CGImage handling, screenshot functions and MDQuery class.