This is a copy/paste of a suggestion I sent in to Aweber.
I wanted to post it here to open it up for discussion.
The theme of it is simple: single opt-in and double opt-in each have their merits. If I had to choose one, I'd pick double opt-in anyday and I know many marketers would do the same. BUT, I feel there are ways to merge them to allow for an even more successful model.
If interested... read the threads below...