A friend of mine pointed me to it. If your application has got a large user base and you need to update from time to time (as with most webapps), you should take much thought on how to run this development properly. A kind of bad example can be studied these days with the online game eve. Since the latest bigger patch one hotfix is hunting the other one and players get more and more frustrated. You can browse the Forums there to get a look even if you do not play the game.
