Let's face it, a dirty email list is dangerous. If left unchecked, the fallout can reflect negatively on your brand and drain vital energy from your business. If your list does get messy over time, it's wise to recognize the symptoms. Here are a few notorious indicators....

The email marketing industry's love-hate relationship with social networks continues. Social networks -- and Facebook, in particular -- were talked about so much during the Email Insider Summit last week that more than one speaker half-joked about it being the Facebook Insider Summit. The Summit began with a panel of Ball State University students, who were clearly gravitating toward email as graduation approached -- but also had a tragically expansive definition of "spam." The conference ended with Loren McDonald of Silverpop declaring, "Old people rule! We pay too much attention to what my 13-year-old daughter is doing."

On the direct marketing landscape, email is as strong as ever. Over the past month, DoubleClick, ExactTarget, and Habeas have released studies testifying to the overall strength of email as a marketing channel. This comes as a response to a string of recent articles claiming that "email is dead." It simply isn't true. Consumers are comfortable buying through email and they feel comfortable receiving permission based email from companies they trust. In fact, across the board consumers prefer email when dealing with businesses for most communications -- and they don't see that changing any time in the near future.

At any time during the presentations, at least half of the crowd was typing away on laptops or smartphones. Many of us had work obligations that wouldn't wait and others were texting, emailing, Twittering and blogging. I found myself so agitated by the pressure to work and blog that I wasn't completely engaged.

Since I seem to be on a semi-roll, challenging long-held beliefs in the industry, I thought I'd throw out another concept: "Preview panes are the new subject line." Now to be clear from the start, I'm not calling for the end of subject lines or suggesting that they serve no purpose anymore. What I am saying is that with the growing adoption of preview panes, the role and value of the subject line is also changing. In fact, the subject line may now be third in importa

Earlier this week, Email Insider David Baker wrote about the dearth of innovation in our industry. I agree: we haven't seen many new things happening within the email space in the last few years. We've all been going on and on about "relevancy," reputation" and "frequency"; it's starting to sound repetitive!

Dear Email Diva: I would be interested to know if there is any data on whether people respond to email alerts marketing (little ads at the end of an alert -- for example, a stock market quote that the recipient pays for), especially if they have to scroll down to see the ad.

I recall not long ago when people in the email marketing business complained there were not enough focused events that highlighted email. I was at a conference just recently and there were a total of 12 people in the email marketing session track, but if you went to the room next door on Facebook it was standing room only. It's really hard to extol the values of a channel that doesn't demo well in a three-minute conversation.

On Nov. 1 of last year, my Email Insider column was about the Achilles' heel of the email marketing industry -- a lack of education, or more specifically a lack of reach for our educational resources. While there are a lot of great resources out there for novice email marketers, including these Email Insider columns, they all require marketers to be proactive and reach out to the community for resources. I wrote, "What about the people who aren't reaching out? These are the people that we most desperately need to reach -- because they are likely doing the most harm …

For an organization to succeed in business, it usually has to employ a variety of different marketing efforts. In large corporations, individual entities or brands often have multiple email campaigns going on at the same time. This can prove dangerous -- or even fatal -- in terms of delivery to even your best opt-in list. Organizations are increasingly finding that the lack of best practices in one area of an organization can cause email delivery nightmares in others.