We'll be releasing an update soon to both text chat and voice communication in the Source Engine that will improve communication for people in multiplayer games. We've completely rebuilt the text chat system, adding the ability to browse your chat history right in the chat window and a filter to remove messages that clutter your game screen. Voice communication will be getting a huge boost in quality, so if you have a microphone sitting on the corner of your desk collecting dust, now would be a good time to plug it back in.