Media queries are about as old as the original iPhone.
Ever since the introduction of that device, existing websites became usable on the modern generation of mobile devices as well.
So while there is technology (media queries, CSS, ...) that steadily becoming more available, so are the mobile devices also getting better at dealign with the content not made for them.
Established websites should all see a pretty sizeable amount of visits from iOS devices. For some reason (don't ask me - I'll qualify as a fanboy for just stating the statistics) while other brands of mobile devices (as a whole) outsell those from Apple, they don't lead to a proportional number of visits - far from it.
So testing how your website looks like in an iPhone/ iPad is important (due to the amount of visitors using it), as it is to test it in different version of IE (if not more so).
Not where does the "hot topic" come in ? Well you could try to deal better with a portrait screen, with a screen so small that the users need to zoom in to read too small fonts and hence get forced to scroll more than is warranted.
This gets worse if you design for ever wider screens on the desktop (and hence put more items next to one another).
So what can you do ?
You can keep more than one layout next to each-other and determine what to hand out based on the viewport size of the browser, that way the handheld device gets something that doesn't require sideways scrolling, while the idiot using a 27" screen in full screen mode gets multiple columns of information instead of text lines that are too long to read.
Alls the rest is hype IMHO.