The IM field is there to store additional information about a user in case you need to contact them. Intervals does not include any chat functionality at this time. We have plans to revisit the client section a little later this year. We are planning to add multiple contacts to clients and also change up the executive user quite a bit so that they can be granted more granular permissions. When we execute this functionality we plan to revisit both the client fields and all of the fields that are available to any user that is created. We plan to add additional fields to make the contact management a little more robust. We do not anticipate a full contact management system like Outlook, but the current features will be enhanced a bit.