Windows RT has a group of apps to work with email, appointments and contacts (including social a messaging system). In the beginning, the Mail application was so limited that it causes a huge rejection and many started asking for Outlook.
Despite the ability to manage multiple email accounts (using imap), Mail Apps missed many important features like select and manage multiple messages (delete, move, etc).
Many Improvements: A few months later, a new releases of Mail, Calendar, People and Messaging was released and I confess email got a huge improvement. It can't still manage tasks.
I still want Outlook RT, but I confess I could live without it once all my contacts, emails and appointments are synchronized between my Surface RT, Windows 8 Notebook, my Windows Mobile 6.5 Phone (yes...I can synch also using my old Windows Mobile Phone) and my Live.com account.
Everything is perfectly synched. I still want Outlook to use with POP email configuration (and not only imap) and also manage my tasks and the integrated environment offered by Outlook.
I use my Surface RT Tablet primarily for business purposes, and then, for entertainment.
Do you want to know more about Mail, Calendar, People and Messaging apps ? Let me know.