By default, webpages created using the Photos and My Albums templates include a Subscribe button. Your website visitors can click this button on your published site to subscribe to an RSS feed, where they can see new photos you’ve published to your site.
If the Photos inspector isn’t open, click the Inspector button in the toolbar at the bottom of the iWeb window (or choose View > Show Inspector), and then click the Photos button.
In the Photos pane, select or deselect “Allow visitors to subscribe.”
When a visitor subscribes, the latest photos published on the website are automatically downloaded to the visitor’s computer in iPhoto. Visitors who don’t use a Mac or iPhoto see the latest photos in their RSS reader.
Allowing visitors to subscribe to an RSS feed of your blog or podcast