Cognitive fluency is - roughly - how easy it is to think about something. Mere Exposure (or familiarity) effects are basically about reacting more favourably to things you see a lot. Which is part of why marketers in generic spaces like insipid mass-market lager will spend quite so much money on getting their logo daubed about the place; or that guy at the bus stop starts to look like a dating prospect after a month or two. Recent thinking suggests that exposure effects likely spin off cognitive fluency. We react favourably to things that are easier to think about. I had to give tech support to an older relative recently, and suggested they Google the problem. They were confused. They could not, apparently, Google the problem, because part of it was that their Google toolbar had mysteriously vanished. Once I'd finished trying not to laugh, I started thinking about typography. This is going somewhere, I promise. Google is a ubiquitous brand. Heck, it's a verb, and their recent, jaw-droppingly well constructed Paris advert is more or less about that ubiquity. It trades on Google's integration into any information-seeking behaviour. But, as my tech support encounter suggests, people settle into comfortable patterns of thinking about things. They build schemas, and altering them can take work. Maybe the ubiquity even works to cement that. Alongside their online effort, Google is running billboard campaigns to advertise Chrome, a free product in a crowded space. They are running these ads in some kind of kooky Calibri / Comic Sans hybrid. Now, at first it seems odd that one of the world's more ubiquitous brands needs to run a big print campaign in public places - surely they have all the fluency they need? Well, not so much. Chrome, after all, is not the same as their core product, so there's some basic awareness work to do, and maybe a whole new batch of exposure effect to try and grab. But why the typeface? It's heavily foregrounded, and the ads are extremely textual. Plus, don't we all know that jovial, off-beat fonts look unprofessional, or something? There's a whole bunch of people who want (often rightly) to ban Comic Sans I wonder, though. Are Google trying to subtly disrupt cognitive fluency? There's an interesting paper (pdf) about - among other things - the effects of typography on they way people answer survey questions. Participants given the slightly harder to read question gave more abstract answers. The paper references other work suggesting that generally speaking, less-fluent question framing elicits more considered answers. The Chrome ad typeface is less fluent for print. Reactions may therefore be more considered, abstract, and disruptive. Is that, in fact, what Google need? They have brand ubiquity, but they want here to change accustomed behaviour, to get people to think about changing their browser. Is this actually a very elegant piece of persuasive information design? If you think about their "what is a browser?" vox pop research video, there's certainly a perceptual barrier they're going to have to tackle somehow.