Agreed, I had a hard time getting the behavior described. Googling for "orange verse tangerine" finally did it. Other things that don't make as much sense to be compared, such as "giraffe verse tangerine" only produce a suggestion of "Did you mean..." but still it searched for my original query.

Seems Google does this for things that are likely comparisons (e.g. oranges and tangerines), which seems reasonable.

I work on Synonyms at Google. We're constantly tweaking our algorithms. It's possible that at one point one tweak made us more aggressive with replacing "verse" with "vs", but then later another tweak made it less aggressive. :-)

Google likes to suggest alternatives to words, he does mean verse as in verse of a song or poem, but (I never saw this particular one) had some searches where google was trying to turn verse into versus or vs. What I saw, and I've either gotten used to it or it's changed, was around 2009 when my searches stopped working one day. I'd use 3-5 keywords and Google's first page would only display pages using 1-2 of them. Invariably it was not the results I wanted. Quoting sections stopped meaning anything to Google searches so searching for phrases became dicy, as the words in the phrase would get split up. So if I was searching for "phrases became dicy" and new that was a line from the page I wanted, Google would return pages with maybe all three words but they'd be scattered about the page.