Startup Idea: Real-Time Collaborative Website Building Platform

Startup idea to develop a platform similar to Google Docs, but for website designing, which would allow a team of IT professionals to build a website in real-time, improving efficiency and collaboration.

I work in IT building websites. One big problem is that a group of IT's can not work on a project all at the same time live. I think a good idea would be something like google docs for building websites where a group of builders can work on a website in real time. Yes I believe many company's would pay for this because it would make projects more efficient.