Saw an article about SteamSpy in my RSS feed and figured I'd look up SK there. You can find it here.
I have no idea how accurate this thingy is but if it's right then something of interest is that SK has an active playerbase of 50k+ players. I would not have expected that!
I mean "active playerbase" is kind of a stretch. The amount of time being put in per player over a two week period had a median of about an hour but an average of about 5 hours. In order for you to play on average 5 hours per two weeks, you have to spent around 25 minutes and then just leave.. which is about the same as logging on, checking the auction house and leaving. It is also forseeable that those five hours could be split between 2 moderately sized play sessions, but this seems unlikely when considering the low median. If you did a couple of runs five days a week and took about two hours to finish you'd have 40 hours per 2 week period. That's what I'd call an invested player- they are going home, and in some of their free time, playing Spiral Knights.
From this and my own personal observations that are absolutely 100% flawless, I would expect a small close knit playerbase that actually cares about the game and keeps coming back to it for whatever reason complimented by an outrageous number of people that are simply trying the game and moving on immediately. The observation in question of course being the distribution of parties I see created as well as the general level of gear I see around Haven- a number of 5* knights, most of which I've met or seen before, and at least as many proto-clad knights, fresh from the rescue camp. Amidst these are typically a handful of 3* knights.
Or maybe I'm just misinterpreting the data and seeing what I want to see.