I find myself these days saying 'cheers' all the time as a kind of mild form of 'thanks', and I heard it said a lot round here (Northamptonshire, England). It's not even a commoner thing, I'd say the middle class are likely to use it a lot. Is it used this way in the US, or would you always consider 'cheers' as something to say when toasting?
Sometimes it is used now to mean "thanks" or "you're welcome" in addition to the toasting context. I live in America and it is catching on, most likely because of the Internet and how interconnected the world has become these days with travel and mobile phones, etc. For better or worse, sayings and distinctions that used to be regional or worldly locators for where a person was from or grew up is not necessarily the case anymore. YouTube, TV shows, movies, friends, travel, and the Internet, etc., can teach anyone anything these days.