SharePoint upgrade from 2007 to 2010 is a fairly straightforward process in comparison to the Performance Point 2007 to 2010 migration. Performance Point pages will migrate to 2010, however, all dashboards will be broken. The recommended solution is to repost a new dashboard on top of the old once. Data sources should migrate by default, however, it is highly recommended to verify all data connections manually after upgrade. Also, user permissions will require manual intervention, especially if Kerberos authentication model was been previously used. Since all objects will be stored in a SharePoint list, Microsoft also recommends going in to it and re-organizing items in a more useful way after migration.
Visio Services has been announced with support for external data sources. This gives those uses who are used to advanced Visio diagrams with data feeds from Excel, SQL and Workflow to publish their diagrams to SharePoint 2010 as 1st class citizens.