Email campaign developers often agonize over the best subject line to use to optimize the open rate. Here’s some data that sugests that streightforward and somewhat boring subject lines work best.
As the author concludes:
Always set your subscribers’ expectations during the opt-in process about what kinds of emails they’ll be receiving. Don’t confuse newsletters with promotions. If your email is a newsletter, put the name and issue of the newsletter in your subject line. Because that’s what’s inside. If your email is a special promotion, tell them what’s inside. Either way, just don’t write your subject lines like advertisements.
When it comes to email marketing, the best subject lines tell what’s inside, and the worst subject lines sell what’s inside.