I\'m being driven to insanity trying to figure out why Intellisense just fails to work at all. The server I\'m using is local and is 2008, the database is set to 2008 compat
Visual Studio 2010 SP1 breaks SSMS 2008 R2's IntelliSense. There is a connect about that, and fortunately there is also a fix for that.
(In short, you will need to install Cumulative Update package 7 for SQL Server 2008 R2 by requesting
SQLServer2008R2_RTM_CU7_2507770_10_50_1777_x86or
SQLServer2008R2_RTM_CU7_2507770_10_50_1777_x64
from this hotfix request page.)
EDIT: As @Paul Lemke noted, one might need to get the latest CU package. This blog contains the SQL server releases. (As of this writing, the latest is CU14)