Mark Spencer presents Motion for FCPX editors at the recent Los Angeles Final Cut Pro User Group meeting. He illustrates with examples the fact that you don't need to know Motion to benefit from its image processing tools in FCPX.
One of the first questions Mark asks the audience at the recent LAFCPUG meeting is how many editors use Motion as well as FCPX. Everybody should says Mark as Motion is good deal for $49 and adds a lot of extra functionality. The following half an hour is especially for those editors who haven't used Motion but can still benefit from features within the app such as advanced keying.
Mark also gives us a good rundown of how the effects are structured within Final Cut Pro X. Motion has been used to write the majority of the built in effects, transitions, generators and titles.
Don't forget that Mark has written the official Motion book that forms the basis for Apple certification. Worth a read even if you are not going to get the certificate, it is packed full of information to get you up to speed.
Many thanks to Mark and Michael Horton of the LAFCPUG.