We’re not looking to be a cheaper alternative to Outlook/Exchange. This means we’re not investing in support for free/busy-style scheduling.
We’re not looking to be the ‘everyman’s’ version of Microsoft Project or Bug and Ticket-Tracking systems. This means we’re not investing in support for complex task and project management, e.g. task dependencies, tracking percent done, time estimates, robust support for assigning tasks, etc.
We’re also not going to be implementing the GTD methodology.