It's still a relatively small market, but the numbers are impressive. MediaPost is reporting that the percentage of mobile device users who view video programming and advertising while on the go has doubled for people using hand-held devices (such as iPods and cell phones), and has jumped by more than 40 percent among people using laptop computers, according to the 2007 edition of "How People Use Mobile Video" from Knowledge Networks/SRI.

Plus, the kind of mobile video consumed tends to depend on the device. For example, while 8 percent of iPod users and 6 percent of cellphone users watch video, the two groups tend to watch different things. According to MediaPost, on iPods, it's more like video behavior on laptop computers, which is to watch longer-form content, while cell phone users tend to watch shorter videos.

Another good quote: "Viewing of feature-length movies has risen dramatically among consumers who utilize the video capabilities of their iPods, jumping from just 1% in last year's study to 54% this year."

It remains to be seen what happens now that the iPhone is thrown into the mix, since the iPhone is both a cellphone and a video iPod -- and a damned good one at that.

Video Begins To Mobilize: Usage Still Small, But Growing Rapidly [MediaPost]