I have promised on several occasions that I will make a post on my blog as soon as an update to VSTO 2005 SE runtime becomes available. Unfortunately when this finally happened I was on vacation and could not immediately post this. My appologies for such bad timing.

Now it is the time to make amends. Please install the new runtime from here if you are still waiting for the fixes to couple of nagging problems like the bug when VSTO add-ins being disabled if Outlook is started in head-less mode (e.g. through automation).

UPDATE (08/31/2007):

As a result of the above upgrade the VSTO2005 SE Windows Installer deployment article has been also updated with the following changes.

• Vista
  Advice is given to help make your solution setup Vista User Access Control (UAC) compliant. This includes new bootstrapper packages for the VSTO 2005 SE runtime and VSTO 2005 language pack.
• Visual Studio 2008 Beta 2 Support
  Office 2003 projects in Visual Studio 2008 Beta 2 continue to use the VSTO 2005 SE deployment and security model. The article has been updated to include instructions on deploying Office 2003 solutions using  Visual Studio 2008.
  Notice that Office 2007 projects in Visual Studio 2008 will use ClickOnce as the deployment & security model.
• Updated detection logic for build 891 of the VSTO 2005 SE runtime
  The bootstrapper package for the 2005 SE runtime is updated to detect the latest version of the runtime. If earlier versions of the runtime are installed, the bootstrapper package will install the latest version.
  If your MSI has a launch condition to search for the latest version of the runtime , then you can update this launch condition to search for HKLM\Software\Microsoft\vsto runtime Setup\v2.0.50727 where Update  >= 2.

The deployment article is available in the usual place