Here's a huge stat that hasn't been getting much attention lately: nearly half of all marketing emails are now being read on mobile devices.
This is a really important trend, so I'll repeat it in a different way. When you send your next email campaign, more customers will read it on smartphones than in a web browser (gmail, yahoo, hotmail, etc.).
Which begs the question: are your emails optimized for opens, reads and click-throughs from all these mobile users?