This is very cool. I assume it's using some form of public key encryption with Steemit keys. I'll be trying this out soon. I don't mind paying a small amount to send a message and that should reduce spam, although we are seeing some spam using small transfers. Maybe people could set a minimum needed to send them a message. Private messages have been a much-requested feature.
Thanks
Indeed, set a minimum amount at least for the wallet notifications would be great. Because I think we are going to have more and more spam.