This and the android device fragmentation (yes, also for resolutions and pixel density) is what pushed me to start replacing raster images for SVGs in all my web and hybrid mobile apps. I guess being quite good at Illustrator helped me to make the jump.

I don't bother using jpg's, png's of gifs anymore. Whenever I can, I use vector designs exported to SVGs (backgrounds, custom iconfonts, logos, shapes, animations, etc...)

That's a great point. I was talking with Doug Schepers and when I noted the resurgence of SVG that's what he said... "oh, I think the Retina screens brought it back" - it is true, SVG is beautiful on Retina screens, there are SVG Test Suite examples where the raster "it's supposed to look like this" image looks very bad next to the SVG side on a retina display. But I think the ubiquity of SVG in browsers was clearly happening before retina screens were widespread. No doubt it is a factor in adoption.