If it's actually beneficial with practically no downsides, it can last a long time, but if there's downsides (eg people getting headaches), probably not as long.  Then again, wee're at the mercy of the companies, so who knows...  If all TVs eventually become 3D, everyone will eventually have one.

When the Wii came out, I thought the motion thing was mostly a gimmick that would get old after a while.  From what I've seen, after the initial hype, that seems to be the case, but there's little downside to controlling with a Wii-mote, thus is here to stay.
Same thought with the iPod clickwheels (personally think they're stupid actually).

(This post was last modified: 04/04/2011 11:44 PM by ZiNgA BuRgA.)