If any of you have used Twitter for any length of time, you might have realized it gets very addicting, and if you've looked at the public timeline, you also might realize that a lot of people use it. Now, if you have really got to be a Tweeter, you've probably also witnessed first-hand that it goes down, a lot. No .. not just once a week, I mean A LOT. One of the big problems that many Tweeters have is the fact that Twitter goes down very often, and if you use Twitter as a means of communication, entertainment, or more, this becomes a annoying occurrence. Twitter Developers have made steps to try to reduce the amount of down time that Twitter experiences, but if there becomes a major spike in users, like say, a mention on a mainstream source, the entire system will most likely collapse. One of the technologies that might allow us to allow Twitter to stay online is a idea from Techcrunch's Michael Remmington brought up on May 5th, 2008.
The key weakness in Twitter (and therefore opportunity for a new decentralized approach) is the fact that so much Twitter activity occurs off Twitter.com. Users are getting very used to using desktop clients (Twitterific, Alert Thingy, Twhirl, etc.), IM, SMS, and other interfaces to talk to Twitter. Those third party applications can be tuned to lock in to the new decentralized Twitter-like service instead or in addition to Twitter itself. - Techcrunch - Michael Arrington
Decentralization is one of the ways Twitter can be freed of the often down time it has. The key to this is to make the 'Tweets' alot like instant messages, where the user would subscribe to a person's tweets, and then the followers would get pinged whenever there is a new tweet. Because there is no single server to be relied on, there in turn could be no site-wide outage. Thus solving the problem.