It depends on what you're looking for. It seems like ComiPo is more aimed for the artistically-impaired manga creators out there but yes, in the long run, it would be best to just stick with Manga Studio if you draw your own work.

Re: video>> Not sure but who knows? Maybe they only had time to show the 3D elements. Anyways, I'll wait till the English version is out to pass judgement. There's only so much that you can know with just reading details about it.