littlebigdetails:

Etsy - uses hidden text to optimize the e-mail preview snippet in Google Mail.

/via Vincent

I just have to point out, this isn’t Gmail being smart, necessarily, but email designers (such as myself, back at ATK) putting it there specifically so that email clients will pick up on it. Gmail especially is SUCH A NIGHTMARE for dealing with HTML and CSS and is almost always the weak point in email tests.

/rant