Update: I've added a section on pre-potting to Advanced Shadow Priest DPS.
As most raiders know, quick voice communication mid-fight can turn wipes into kills. As such, a reliable voice-chat program is a must for most raids. While WoW does include a voice-chat feature built into the game, it has several major flaws, such as poor sound quality, and high latency in groups of more than 5. Ventrilo is the most popular voice-chat program, followed by TeamSpeak, and my personal favorite, Mumble.
Mumble has two main features that make it better than Ventrilo: lower network usage, and automatic volume adjustment. The main thing holding it back is Ventrilo itself; since Ventrilo is so popular, very few people know how to use Mumble, and so, Mumble is harder to use because you need to walk people through using it. In this post, I'll present a simple guide to connecting to a Mumble server.