<p>Given that we have at least a few vision-impaired readers who have mentioned this fact on our site (and no doubt many more who don't post or don't mention it), I think we should attempt to add at least brief alt text as a matter of course -- it's just a matter of replacing "enter image description here" with a description of the image. Even a brief one-sentence description is better than none, though longer descriptions are better still. Alternatively, describe it in the text of the post.</p>

<p>As for what to do with old posts I certainly suggest adding a description if you happen to be editing a post, but I wouldn't necessarily start a wholesale rewrite of old posts because we would bump thousands of posts. We should really only bump a few a day, so it would be years.</p>
