[amikazmi]

I feel exactly the same- let users use and require sing-up for saving data etc.

But for young applications, it is important to get in touch with the users, and try to engage them-

There are some start-ups dedicated only to automatically send users email after some conditions, and most of the service I use do it manually too (like sending you "we noticed that after you built your form you didn't publish it for a month, care to tell us why?")

If you don't know who your users are, how can you get the negative feedback?

Getting feedback only from the people who sign up is going to be skewed to the positive side, and you'll have a problem realying on analythics for guest users (because some "guest users" are can be the same user- from different machine, or after cookie clean)