Have to agree with the previous two posts. By the time you're ready to think about filming underwater, you should have done so much diving that equipment choices were made long ago.
There are few things worse than having to sit watching ill-thought-out videos shot by poorly skilled divers. Get the diving right first, then you can actually concentrate on the shots you want and how they'll work together to tell a story. Don't get a cert, get a camera, jump in and point a camera at the same subject for ten minutes and then show that, unedited and with loads of high-speed pans and vertical wobbles. Doesn't work, and is a waste of your time and effort (and money) in my opinion.
I'd have to take issue with yarik83's post. You concentrate on the DIVE, you don't dive through your camera. See the shot coming, get set up, concentrate on getting 15-20 seconds of good footage of whatever it is (nobody will watch a single shot for longer, unless it's something truly spectacular), check your depth, time, deco or non-deco status on your computer/tables/run-time/whatever. You don't need stacks of d-rings (what on earth do d-rings have to do with shooting video?) and - while a rebreather can help you get closer to skittish subjects, since there are no bubbles - good dive skills can also get you there. It's all about being still in the water, and that simply comes with hours (and hours and hours) of diving.
As to recommended BCs? Whatever you want. Won't make a blind bit of difference, as long as you're comfortable diving in it and have the skills, especially buoyancy control, to keep the camera steady and have the situational awareness to manage your dive safely and see good shots coming before they happen.