Recently intellisense in the SQL Server management Studio stopped working.
It appears that it was caused by the installation of Visual Studio 2010 SP1.
It was originally suggested that this could fixed by SQL Server 2008 R2 Cumulative Update #6, but this in turn lead to a crash in Visual Studio 2010 when ever you opened a .sql file in your database projects.
It suggested that this issue has been fixed and will be released in SQL Server 2008 R2 Cumulative Update #7, which was due out in Mid April.
You can install Cumulative Update #6 and in most cases this will get intellisense working in SSMS but it will break Intellisense (on database projects) in VS2010.
So if you are like me, you are between a rock and a hard place, your choice of which environment you prefer to have working.
Lets hope that CU #7 fixes it.
I will update this post with my results after I have applied CU #7.
Update as @ 19th April
Today Microsoft has released Cumulative Update package 7 for SQL Server 2008 R2
After downloading and installing, preliminary results are that the problem is solved.
Intellisense in SSMS seems to be working and I no longer get the crashes in Visual Studio 2010 and Intellisense in Visual Studio 2010 database projects also seem to be working correctly. So, so far so good.
Update as of Nov 2011
As someone has pointed out the release of SQL Server 2008 R2 SP1 is supposed to fix this issue, (as it contains all the rolled up cumulative updates).
I personally have had mixed results with some machines working again and others having “Intellisense” working in SQL management Studio but remaining broken in Visual Studio 2010. My main work Development environment is still broken in this way and if I ever get it working I will udpate you on what I had to do, but for now I am living with only having intellisense in the SQL management studio.