A W3C Candidate Recommendation as of 27 July 2010, we have seen browser support for this develop over the last year. Not only can the media component of stylesheets be used to specify an output device or medium, now we are seeing ways to specify the dimensions and orientation of that device.

As always, we try to distill the the most functional aspects from the specification. This is not academic for us and we do mean “real world” usage. What we take away is this:
Use min-width to determine how many columns a website should lay out with. This can be useful in the case of a design-once and view-anywhere type of website that, not withstanding bandwidth requirements, will look good on wireless devices that have a lower maximum screen resolution.