Stumbled upon this interesting article.

Integrating Visio 2007 and Project 2007

Summary: Microsoft Office Project 2007 and Microsoft Office Visio 2007 provide integration capabilities that previous versions did not provide. You can take advantage of these capabilities by using a combination of native features and COM add-in features.

This article from MSDN net say you can have real good integration between MS Project 2007 and the project planning diagrams in VISIO. Its wonderful in the sense that you can add some visual treat to the ease of managing the project.

The feature that creats a timeline in visio from a WBS in msProject is really great.

So are the possibilities of using the new pivot diagram features in visio 2007 with data crtical data from Project(like effort, cost etc.)

However i should mention that all this is possible only by using an add-in "Visio Connector for Project/EPM/SPS"