I agreed with the design and development philosophy laid out by Dave Rupert in the latest issue of A List Apart:
Those of us involved in CSS and Web Standards groups are well acquainted with the concept of progressive enhancement. It’s important we stick to our collective guns on this. Pixels, whether in terms of device real estate or device density, should be treated as an enhancement or feature that some browsers have and others do not. Build a strong baseline of support, then optimize as necessary. In fact, learning how to properly construct a progressively enhanced website can save you (and your clients) lots of time down the line.
His core methodology for handling responsive images is simple: Rely on CSS first, SVG and icon fonts secondarily with the picturefill as a final solution.