goodroi - 7:03 pm on Oct 26, 2012 (gmt 0)
Imagine searching for "Ran Kings" you would expect to see pages about royalty. But "rankings" is a completely different idea and users would expect to see something very different. This is a bit of an extreme example but it shows how adding an extra space can make Google's automated process think they should show something different.
For obvious typos Google may show similar results but don't suprised if an extra space delivers slightly different rankings (like rewarding a website that also has that typo on their page). Personally I wouldn't worry too much on this since IMHO there are much more powerful pieces to the ranking algo.