There are plenty of standalone apps for videoconferencing. I don't think there's any need to package it with a whiteboard app unless you can come up with an innovative way to integrate the video with the whiteboard (indexing video frames to scribbles, maybe?)
In my experience, having a video feed is pretty much worthless for productivity; if anything, it's distracting. Much more useful is having voice chat and the ability to share files seamlessly. Again, these are needs that can be adequately fulfilled by Google Docs, Google Talk, Skype, etc, so there's no reason to reinvent the wheel.
This is exactly the approach we're going for. We're a distributed team and have been since the start, and over the past two years we've used a variety of weird and wonderful tools to enhance the communication between us.
While video conferencing is nice, we've never found it really adds that much value to our conversations unless we're show & telling. Screen sharing can be useful but it doesn't lend itself well to a fluid two-way conversation (only one person can control a computer/cursor/keyboard at once), and it's generally not instantly available - if we're already talking on the telephone we have to switch tools entirely, and if we're talking to someone outside our team it's pretty much pot luck as to whether they'll already have access to the same services we do.
We wanted something with zero setup. No registration, no downloads/installs, no login.. Maybe when HTML5 is implemented uniformly across all major browsers we can drop the requirement for any 3rd party software at all.
It's an add-on to your existing workflow, rather than a workflow of its own.
http://imgur.com/dBP1u.gif
http://i.technet.microsoft.com/Cc723477.nm3feat2%28en-us,Tec...
Netmeeting also had video conferencing and chat to go with it, though.
http://www.microsoft.com/PRODUCTS/internet/netmeeting/demo/w...
Maybe you could partner with Chat Roulette ;)