Sitemaps has truly been a basic SEO step for many large or even medium sized web sites. Google Image search has been a strong driver of traffic to many sites, but sometimes it is hard for webmasters to get their images indexed. Google announced support for images in Sitemaps.
Here is an example:
<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
xmlns:image="http://www.google.com/schemas/sitemap-image/1.1">
<url>
<loc>http://example.com/sample.html</loc>
<image:image>
<image:loc>http://example.com/image.jpg</image:loc>
</image:image>
</url>
</urlset>
With this you can specify image, location, caption, geolocation, title and license. For more details, see this document.
Forum discussion at WebmasterWorld.
