Wordpress ought to do that for you. It has both RSS feeds and email notifications (last time I looked.) Just install a WP announcement blog.
For fee there is Micro.blog Premium for $10 per mo., which has both RSS and JASON feeds plus newsletters.
All the features of a hosted microblog, plus...
Up to 5 blogs
Email newsletters
Private and shared notes
Bookmark archiving and highlighting
Podcast and short video hosting
iPhone app Wavelength for recording