Although I have never being involved in such an event yet at least from the point of firing someone well from being fired as well..heh. I think I can relate to it as I have worked in companies which was forced to fire someone due to non-performance. In the end, It kind of hit home and created a morale issue. Anyway a great article on it is written here. Firing is never easy.
This link came by the way of OnlyOnce a blog that can be accessed from my right menu under Startup/Venture. Always an interesting read, those articles are like going through school and learning for free if you ask me.