However, Wave's appeal extends beyond e-mail and IM, since it also offers a wide variety of other functionality, like blogs, wikis, photo management and document collaboration, and can be extended broadly by third parties thanks to its open architecture and APIs, he said.

"It glues together a lot of things that have until now been separate products," Dulaney said. "This is where users will want to be."

Even after working on the product for about two years, Rasmussen and the other members of the Wave development team still discover new uses for the tool, so he's very aware that grasping the possibilities of Wave will not be an automatic thing for end users.

That, again, is why Google decided to share Wave early with developers. "Now is a good time for developers to start picking up the APIs, building cool applications and extensions, so when we do launch later this year our users and their users can enjoy all these things together," he said.