That video reminded me of this YouTube video about shooting BRoll for a documentary. The one thing that I think this guy missed in the video that this video highlights is using b-roll to do more than just cover the cuts of your interview but also help tell your story.
I think that the irony of 4k is that as it gets more and more popular and cheaper to use the more people are watching videos on device that get smaller. With that being said I think that their are pros and cons to shooting on 4k. The biggest con is that until recently there haven't been a lot of 4k devices to watch anything on. This year though a lot of manufactures have released 4K tvs and I expect that they will sell a lot of them this Christmas season. The other con is that you need a nice computer to work with it. I work on a Macbook Pro and can handle any 1080 footage but with 4k everything slows down. Of course - if you are an editor with a nicer computer than mine (which is probably the case) than that really isn't a problem.
The pros of 4k is obviously that you get more pixels to work with and if you can broadcast on a 4k device it looks better than 1080p. Also with more and more people getting things that they can actually watch 4k soon more people will be expecting 4k. Remember when YouTube started playing HD videos? When that happened not everyone was releasing HD videos and a lot of the videos can only go up to 480p on YouTube. At the time it was no big deal. Now though when people go to a video and see that it's max resolution you think, "how old is this video?" I think if anything 4k will eventually catch on and be a standard just like HD did a few years ago and 6k or even 8k will take the place of 4k. If you want to be a future proof filmmaker I think that 4k is the way to go.
I think that this is a great step forward for all independent filmmakers but the struggle that this is going to have is that they don't have a lot of viewers yet. Don't get me wrong - it is still a service that I plan on using for my feature length documentary but it is going to take some time for this to catch on and become a very valuable tool for indie documentaries.
I think that everything that everyone has said is great advice but one thing that I would add is focusing on the design. I think that one of the reasons why Sherlock's text messaging is so great is that it is simple but still designed well. If you don't have a background with design try finding some blogs that talk about typography. Together with the motion tracking you will get a great result.
Philip Bloom did a video for Canon Pro talking about the DAF upgrade with the C100 (http://www.usa.canon.com/cusa/professional/standard_display/eos_c100_fea...) and he did a pretty good job explaining it.
By the looks of it - the dual auto focus is really good except that it works only when the subject in the center. Fortunately you can press a button and hold focus so if your subject is moving to one edge of the frame it will still hold focus.
240 FPS? I can see people getting an iPhone and just use it as a slow motion camera. Even if you bought it out of contract it would still be cheaper than any other camera that can shoot 240 fps at 720 (besides the GoPro).