I see people suggesting going with SVG or resizing a high resolution image, but there was a good post not long ago about the problem with SVG and blindly resizing. You really need your images tweaked on a per-size basis.
I can imagine you can get away with automatically resizing iPad HD -> iPad, but going down to the relatively tiny sizes for the smaller screens would be a bad idea IMO.
I see people suggesting going with SVG or resizing a high resolution image, but there was a good post not long ago about the problem with SVG and blindly resizing. You really need your images tweaked on a per-size basis.
I can imagine you can get away with automatically resizing iPad HD -> iPad, but going down to the relatively tiny sizes for the smaller screens would be a bad idea IMO.