Feature Descriptions:

MAPI / ActiveSync
        Directly Synchronize your online mailbox, online calendars, and online contacts with any enabled mobile device, Microsoft Outlook or other supported mail client.

Cloudmark Protected
        Protection against spam, phishing, virus, malware laden email messages
        Industry leader in online security
        Largest subscriber base for any spam filtering solution
        2 billion subscribers (email accounts)
        Used by many large carriers and organizations
        AT&T, Comcast, MySpace, NTT, Swisscom, Time Warner, SUN, Openwave, and others
        http://www.cloudmark.com/en/company/index#cpart

DDoS Protected
        State of the art protection against network and system attacks
        Used by Papa Johns, Traveltainment, Produban, and others
        http://www.radware.com/Company/Customers.aspx 

Cloud Infrastructure
        Your email is hosted and maintained on the latest in cloud computing hardware and software technology

Advanced Webmail
        An advanced online interface for reading and sending email, maintaining your list of contacts, and operating your calendars and shared calendars.
        Has a look and feel similar to most email clients (like Outlook or Mac Mail)
                Address Book / Calendar
                        Maintain your list of personal and business contacts.
                        Maintain your personal or shared calendars
                        Sync your contacts and calendars
                        maintain directly with any supported device or client
                                *must support MAPI / ActiveSync
                                Outlook (mail client)
                                Mac Mail (mail client)
                                Zimbra Desktop (mail client)
                                iPhone (and iPad)
                                Android (phones / tablets)
                                Windows Mobile (phones / tablets)

Calendar Sharing
        Share your calendars and invite others to meetings

IMAP/POP3/SMTP
        Connect to your mail account with these supported protocols

MAPI / ActiveSync
        Connect to your mail account with these supported protocols
        Synchronize your email, calendars, and contacts with supported mobile devices

Briefcase
        Store files in your briefcase or share them with others
        Use with webmail and Zimbra desktop mail client only

Collaboration
        Collaborate with others on folders, tasks, and calendars
        http://www.brinkster.com/Solutions/Hosted-Email-Collaboration.aspx 

Mobile Device Wipe
        Mobile device security configuration
        Managed through webmail - remotely wipe / delete / reset mobile device. For use with lost or stolen mobile devices.