On April 21, Google began to change its algorithm for mobile searches. Websites which aren’t mobile-friendly (big buttons, uncluttered text) were penalized, dropping in rankings of searches done on mobile devices. Google constantly tweaks its search algorithm to make sure the most relevant content shows up on top.
Google released a guide detailing exactly what it’s looking for in terms of mobile-friendliness. And unlike with previous algorithm tweaks, Google let users and developers know months ahead of time about the change and promised a slow rollout, so as to avoid dramatic overnight changes. But this change still caught the public’s attention. (Unless you’ve never heard of this before, in which case it at least caught Matt Drudge’s attention, and the attention of all of these lovely people on Twitter.)