Email reputation: what is the expiration date of your opt-ins?

... sure that your recipients are actually interested in your emails. But although you are now complying to the email marketing legislation, these efforts aren't enough to prevent that you'll be regarded as a spammer. An opt-in's sustainability isn't ...

http://econsultancy.com/us/blog/62557-email-reputation-what-is-the-expiration-date-of-your-opt-ins?