I've noticed this for a little while now and thought I'd post it for discussion. Normally on a cache the terms are highlighted. In this case however, they are not even though they can plainly be found on the page.

Confirmed. I see what you mean.

Ill try to give some examples...

Ok, I dug up an example.

http://www.google.com/search?hl=en&lr=&q=site%3Awww.seroundtable.com+TrackBack+URL+%22Dis cussion+on+Google+Indexing+Itself%3F%22&btnG=Search

Should highlight 'Google Indexing Itself?' but it is not. There are many examples, but I wanted to use one that wouldn't make fun of a site that wasn't mine.

Cache URL: http://72.14.209.104/search?q=cache:8-7H50Grbq0J:www.seroundtable.com/mt-tb.cgi%3F__mode%3Dview%26entry_id%3D3073+site:www. seroundtable.com+TrackBack+URL+%22Discussion+on+Go ogle+Indexing+Itself%3F%22&hl=en&gl=us&ct=clnk&cd=1

The thing that really struck me was the words are on the page. Note this only seems to be happening with supplemental results and not the regular index cache.