YES I'm with you on this one!! I would personally love to see this feature implemented.
Also, I was also just thinking the other day that it would be awesome if you could set up RSS feeds and push notifications for whenever your favorite Steemians post new content. I found Streemian.com but it looks like it is a paid service for some of the features that would be most helpful.
Is there by chance a Steemit app for Android? I was looking on the Play store and the only thing I found is an app called eSteem which looks like it is based on the STEEM blockchain but it doesn't look like anything official.
Thanks! Yes, notifications and app will definately boost number of daily sign ups