IFTTT (If this than that) Integration
It would be nice to have more notification options and to connect other people more into the challonge service. Alle that could be easily accomplished via www.IFTTT.com
With a Challonge Channel we could create our own recepies (e.g. insert an appointment in my google calender when my match becomes available, tweet about match results, send push notifications, etc) to get more involved into our tournaments.
Since the Challonge API seems to be really flexible, it should be easily integrated with IFTTT - somebody "official" only has to inquire support for it on IFTTT.com -> https://ifttt.com/platform