I'd really like to be able to see the options and create pull lists etc before signing up. Right now I have no way of judging how good/bad the service is without signing up - and I don't feel comfortable giving up my email id without having a sense of that value first.

Also, allowing me to interact with the service prior to signing up would lead to me investing some time/effort which would go to waste if I didn't save it all by signing up.

Hope that helps.