If there's something I think is valuable and useful I have no issue paying with a tweet—and if you've got a SaaS business this one's more than worth a tweet (even if you think you know your shit it's a great resource to review), and I think the people that read my stream might find it interesting too
i usually don't mind sending a tweet to get free stuff. i did it to get an awesome free font the other day for example.
what bothers me with this site is: after sending the tweet you are not done. you still have to create an account first. and the "login" function via twitter redirects you to a sign up page. whats the point of offering single sign on services if users have to fill in a signup form afterwards? btw. i'm 5 minutes into to process and still haven't gotten to the content.