Basically to get me to click it, it needs to be something I'm into.  If its an interest cheque of a particular genre or fandom, I'll click it.  

To get me to Join all I need is several good paragraphs to show me you can write well and you've thought out the basics. (Who, what, when, where, why and how)  A little something about the potential plot helps a lot.  

At the end of the day for me an interest cheque is just that, it's the baby of the idea not the final form of it.