Well good news. Zooomr released Zmail today (our internal email system). Zmail is not meant to replace your regular email but is designed to be used within the social community of Zooomr.
If you have a Zooomr account shoot me a zmail the next time you are on Zooomr. Features in zmail include: support for multiple recipients, a nice rich text editor (italics, bold, hyperlinks, etc.), a notification system that lets you know when someone opens your zmail, and a really easy compose system that auto suggests recipients as you begin typing their name.
More on Zmail on the Zooomr Blog here.