Google's John Mueller answered a question in the Google Hangout at the 19 minute mark about is it better to go with short or long URLs. We know Google said don't go over 2,000 characters in your URL and we know Google may try to shorten your URLs over time.
In short (no pun intended), John Mueller said that when Google notices two URLs on a site with the same content, it will tend to go with the shorter URL.
He said:
Short URLs or Long URLs?What definitely plays a roll here is when we have two URLs that have the same content, and we try to pick one to show in the search results, www ill pick the short one. So that is specifically around canonicalization.
It doesn’t mean it is a ranking factor, but it means if we have two URLs and one is really short and sweet and this other one has this long parameter attached to it and we know they show exactly the same content we will try to pick the shorter one.
There are lots of exceptions there, different factors that come into play, but everything else being equal - you have a shorter one and a longer one, we will try to pick the shorter one.
Here is the video embed at the start time:
