if you are having trouble getting intellisense like I did with VS 2008 here are the steps that you can take

download the bdcmetadata.xsd from following url and copy the file to “c:\program files\Microsoft Visual Studio 9\xml\schemas” directory (assuming VS was installed on “c:\program files\microsoft visual studio 9” directory)

Remove the “xsi:schemalocation” attribute from the root node of your application definition file, if one does exist

Restart Visual Studio