I think sites designed on the "mobile first" concept will be the latest trend.
Try resizing you browser width on the MyBB main site to see an example of mobile friendly design.
Try resizing on
http://www.timeslive.co.za/ so see a site that is not mobile friendly.
I am currently working on a mobile friendly wordpresss design that has 7 design styles based on screen widths of various devices.
Takes quite a bit of time to do as you are in effect styling a website mutiple times for multiple devices. (phones, tablets, desktop in portrait and landscape.)
Gets tricky whe you are using columns that must play nicely for all screen sizes.
I work with 4 columns on large displays and then scale to 2 columns then scale to 1 column depending on screen size.
4 -> 2 -> 1 works nicely
Other colums style get a bit messy