BTW, I held one, definitely heavier than the regular P4, and the gentleman working there says it's a bit bigger. Really awesome looking though with all the sensors. I'm tempted, but will wait for the Mavic. The convenience factor is huge.
If you want portability then you definitely want the Mavic. I flew with mine in my briefcase with my full Micro 4/3 kit yesterday. If you don't need portability the P4P looks like an amazing machine with a top notch camera.