Visio has some great "mash-up" capabilities, which enable it to easily be integrated into SharePoint 2010. To create a simple Visio Web part diagram, follow these steps:
1. Open Visio 2010. Click File ➪ New and then select the ITIL Diagram.
2. Create a diagram.
3. When you finish building the diagram , click the Backstage tab (the tab on the upper-left part of the Visio document) and then click Share. At the bottom of the Backstage view, select Web Diagram. Note that, after you've finished, when you click Save As, there is an Options button that you can click to see
what pages (if you have multiple pages in your Visio diagram) will be published to Visio Services.
4. Next, upload the Visio diagram to a document library.
5. Click the drop-down menu beside the uploaded document and select View Properties.
6. Select Copy Shortcut.
7. Navigate to the location where you want to add the diagram on your SharePoint site, and then click Site Actions ➪ Edit Page.
8. Click "Add a web part" (or, if you're on a wiki page, click the Insert tab and select Web Part).
9. Navigate to the Office Client Applications, and select Visio Web Access Web part.
10. Once it is added, you can edit the Web part using the tool pane. Specifically, you want to copy the shortcut to the Visio diagram into the Web Drawing URL file and then click Apply. The Visio Web drawing will now be rendered in your SharePoint site.