Apparently the voice chat service will be also available just through Sony's Launcher, so you won't need to be in-game to use the applications. Gamers will have buddy lists, and games will all have volume controls and channel controls, but the other features they brag about apparently won't be available at launch-- while voice and guild chat channels will be available right away, the other features, like voicemail and "voice fonts," are only "anticipated" for later. Still, John Smedley, SOE President, is quoted in the release as being excited about bringing the two services together, so only time will tell how it will all work.
Time, and our interviews, that is. Massively has a few correspondents on the floor at GDC right now, and we are planning to speak with both Vivox and SOE before the end of the week. Stay tuned for more on these services and just what they'll entail for players in-game.