Why make your users pay attention to what changes on your site? Let the website do it for them.
With a clever combination of a few scripts, you can allow the page to highlight what has changed from the last time a user visited the page.
Go visit the example page and see for your self, then come back here and find out how it works.
How it works:
<li> elements, it will pick get the string
"This is a test" from
<li>This is a <strong>test</strong></li>. (I lied It also strips out whitespace).
Next it sends those off to a server side script along with a unique id which gets tagged in a cookie. The server side script just checks your memcached and if all the hashes are new, it just stores them. If only some of the hashes are new, it will return those.
Back on the client side, if it get's any hashes back (meaning you haven't seen the corresponding string of text before), it will go highlight that block using the Fade Anything Technique.
Thats it =)
Implementing TrackChanges.js on a page is as easy as this