For as long as I've been writing about VoIP I've been saying that it's the apps that matter. It seems one of the more veteran VCs in Silicon Valley is on that page also.
The app she's referring to in the Business 2.0 story by Michael Copeland isreally a VoiceXML type of application that shouldn't be that hard to do. Parus Interactive already has lots of this type of technology and may actually hold some patents that put them in the cat-birds seat on this one.
Other companies are starting to hit this sweet spot and likely will be bubbling to the surface at Fall VON or even sooner, next week at VoiceCon here in San Diego.