Does the world really need a new descriptor for voice mail and conferencing?
Look, there's a new metaphor for communications, and there's a new way of implementing real-time IP communications that changes the game. So, just like PCs are not just Computers, Convergence Applications are not just Applications.
The Convergence part of this category is based on the idea that a unified voice-data network is the reason for the application. The network with PoE, and with QoS, is the key enabler for the implementation. It's not just IP. Besides, the purpose of language to be precise. Ergo, the convergence applications are describing a new set of communications services that help.