Okay so this isn’t “new” BUT it is still amazingly relevant and great information from Ajax Union.  Here ya go and thank you Ajax Union for letting me repurpose this post:
As we’ve mentioned, email marketing can be tricky — a lot can go wrong. We’re going to list some of the most common mistakes email marketers make, so you can avoid them.

Buying Email Lists: We’ve discussed this before, but let’s delve a little further into why it’s such a bad idea. Say, for example, you receive an email from a company you’ve never heard of and just aren’t interested in. Maybe you’re signed up for a similar business newsletter, or maybe this new company just isn’t your bag. Either way, you want out, so you unsubscribe. You might even mark it as spam or send an official complaint.
Now, imagine 100 other people do that. Mailchimp and other email service providers (ESPs) will notice your high unsubscribe rate and possibly shut down your account. You’re much better off growing your list the old-fashioned (i.e. not sketchy) way.
No Opt-Outs: “But if there’s no unsubscribe link, my unsubscribe rate will be zero! Muauahahaha!” No… just no. You need to give people the option to unsubscribe, or they will do the online equivalent of chase you down with pitchforks.
Typos: Before you send out an email, please, please, please proofread it. Then proofread it again. Then send it to 2-3 other people to proofread. You might be surprised by how offensive a rogue “teh” can be, but trust us — typos are a major badge of unprofessionalism.
Not Tracking Your Links: Google’s URL Builder makes it incredibly easy to track your conversions and open rates, thus seeing just how effective your emails are. Seriously, it’s super simple. There’s no reason not to use it, so use it.
Boring Subject Lines: When crafting a subject line, imagine you’re applying for a job. You would never start with “I am applying for this job,” because a.) you’re not a robot, and b.) anyone who reads that opening line won’t be able to finish it without abandoning your application for a rousing game of Angry Birds. Be personable (not unprofessional) and engage your audience. (Tip: Puns are almost always a good idea.)
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