Odd cache highlight glitch + rank drop

Google cache highlights terms incorrectly

[icarus]

Just noticed one of our more popular pages suddenly drop in ranking substantially a few hours ago. The only thing I could find is that the Google cache highlighting of search terms that appear on that page is rather screwy.

For example, let's say my search term is :

bargain blue widgets

and on my page is the text :

we have bargain blue widgets for sale

When I click the Google cache link for the listing and check out the G highlighting for the terms, I'm seeing stuff like:

ave barg

or:

ets for

highlighted instead.

Same happens for any term I use in relation to that page; even totally different terms.

Pages that don't have the ranking issue have correct word highlighting when viewing the Google cache. I'm still hunting around for other page examples on the site to see if this just a coincidence as I think a few other pages may have suffered as well. Anyone seen this kind of thing happen before?