I'd like to suggest Calendar and groupware integration as a Feature to round out LinuxMCE's feature set. Integrating groupware like Zarafa, Zimbra, OpenGroupware.org, php/egroupware, or another similar groupware package to leverage it's calendar, tasks, contacts and integrate that functionality into LinuxMCE. Plus, you could leverage a mobile sync solution like zpush (Open-Source ActiveSync implentation) or Funambol (SyncML), would allow for the integration of mobile devices with the same datastore as in LinuxMCE (and vice-versa). The idea would be that calendaring/task/contact and sync functionality would be handled by their respective projects, and LinuxMCE would wrap it's functionality much like MythTV or Xine, either with wrappers or API calls.
You wakeup to an LinuxMCE alarm. The system reads you your daily appointments as you get ready in the morning.
Your mobile device is synced against the DataStore shared with LinuxMCE. Contacts you have just added to your mobile device are now available to the Asterisk Telephony system. Birthdays listed in your contact's information are announced a predefined period of time in advance.
LinuxMCE's behaviour is modified by categories or keywords found in your calendar. For example, you set an earlier wakeup time in your calendar due to attending a seminar, so LinuxMCE automatically starts your morning wake-up routine at the earlier time, rather than at the regularly scheduled time. You have a party at home, so LinuxMCE automatically engages entertaining mode.
Hopefully this is some food for thought...