You can now use SendTo (version 1.1.1) to send clips from Final Cut Pro X to After Effects CS5/5.5/6, as well as Motion!
Here’s how it works: export your FCPX project as .fcpxml, drag it onto the app, and select the clip you want to send. Then click “Send To” to setup a composition preset with in/out, duration, frame rate and resolution in Motion or After Effects. It’s a great way to save time setting up compositions, and get right to work on grading, effects, etc.
Now available as free software under the MIT License.