Is it absolutely necessary to have an account? Rated 3 out of 5 stars
I know from reviews here and in the Apple App Store that there are a growing number of people who don't like to have to open accounts in order to use an app or add-on. So I suggest that the developers make it very clear in the description that a membership is required to use this add-on. It would be better for them because they won't have customers who are surprised (and likely annoyed) by the requirement after they have installed Zemanta.