Since we watch videos on computers and mobile devices and slates - the notion that a video must be presented in a landscape aspect is going away quicker than your cable TV bill.
TVs are landscape.
But we are so close up to our computer devices that Portrait mode is coming down the pike as a new way to view moving images.
Have you been taking cell phone video on your iPhone? It just feels natural to hold it in one hand in portrait mode.
Take adavantage of Portrait mode in your next video...
I found this little film by Rick Hamilton on vimeo that takes advantage of being vertical. It feels like 4x6 home photos come to life.