Yes, i know of built in uml that i did at uni that i used in vs2010 :) It was great and such an aid to the final year project that was a requirement for a developer in the initial stages of development.
For sharepoint I would presume your talking about linq:
SharePoint 2010 offers many new opportunities to developers, and
especially with LINQ to SharePoint. This technology brings a greater
flexibility to the developpement model to use more easily the data
contains in the SharePoint lists. Now to make a query in a SharePoint
list is as easy as making a query within a database table, thanks to a
real object relational mapping process. This tool generates SharePoint
classes (like the command line tool SPMETAL) directly in Visual Studio
as a design schema (like LINQ to Entities). This new feature is an
extension to Visual Studio for modeling LINQ to SharePoint entities.
With this tool, it’s become possible to add a new kind of item in a VS
project, called a LINQ to SharePoint schema (or LINQ to SharePoint
hope it helps :)