I have visual studio 2005 and 2010.
I install oracle developer tools "ODAC112011beta" for visual studio.
I can use this tools from visual studio 2005 but i can not see this tools from visual studio 2010.
First of all, when you ran the Oracle installer, did you select "VS2010" when it asked you which versions of VS you wanted to enable?
Are you using the release version of VS2010 (not the RC or beta)?
Finally, when you connect in Server Explorer, do you choose "ODP.NET" as the datasource? See this screenshot: