Just a quickie - a user of the non-3D version. Actually I didn't know exactly what I'd use Timeline for, but the potential was so extraordinary I made the buy - I've used it for two projects now and I'd rank it with Comic Life - it's that well done/cutting edge - pure Mac - integrates with everything seemlessly. Actually, Apple should do what they did with C.L. and include Timeline with new Macs. It's definitely a switcher app.
You'll stay up nights trying to come up with projects just so you can use it.
The two times I've emailed Adam with questions, the answers came back within hours.