2009/6/23 Remember the dot rememberthedot@gmail.com:
Hello fellow developers,
In Håkon Wium Lie's recent analysis of Wikipedia image markup ( http://www.princexml.com/howcome/2009/wikipedia/image/), he makes a good point: we include image captions both below images and again in the images' tooltips.
This is actually only the case if you use the keyword 'thumb' or 'frame'. If you just do [[file:foo.jpg|this is my caption]], then you only get the "tooltip" (usually called "alt" text for images). http://en.wikipedia.org/wiki/Alt_attribute
You may be interested in reading this English Wikipedia guideline, as part of its Manual of Style: http://en.wikipedia.org/wiki/Wikipedia:Alternative_text_for_images In short, alt text is important for accessibility.
Also, for inline images without explicitly defined tooltips, the
image name is used as the tooltip even though it is also shown in the URL when mousing over the image. Neither of these automatic tooltips are really useful, and they slow down page load time on image-heavy pages.
They might not be useful for you, but they are useful for others. On what basis do you say they slow down page load time? I would be surprised to find that supplying or not supplying alt text made any difference.
Brianna