I also cannot load Search Work Items properly. If I launch VS.NET with the /log switch, here are the Search Work Item related events:
<entry>
<record>44</record>
<time>2009/06/03 21:07:44.048</time>
<type>Information</type>
<source>Microsoft Visual Studio</source>
<description>Loading .NET AddIn: SearchWorkItems.Connect</description>
</entry>
<entry>
<record>52</record>
<time>2009/06/03 21:07:44.376</time>
<type>Error</type>
<source>Microsoft Visual Studio</source>
<description>Calling OnConnection for Addin: SearchWorkItems.Connect</description>
<hr>80070057 - E_INVALIDARG</hr>
<errorinfo>A Command with that name already exists.</errorinfo>
</entry>
<entry>
<record>53</record>
<time>2009/06/03 21:07:44.376</time>
<type>Information</type>
<source>Microsoft Visual Studio</source>
<description>Unloading AddIn and calling OnDisConnection: SearchWorkItems.Connect</description>
</entry>
<entry>
<record>63</record>
<time>2009/06/03 21:07:46.079</time>
<type>Information</type>
<source>Microsoft Visual Studio</source>
<description>Loading .NET AddIn: SearchWorkItems.Connect</description>
</entry>
<entry>
<record>64</record>
<time>2009/06/03 21:07:46.095</time>
<type>Information</type>
<source>Microsoft Visual Studio</source>
<description>Calling OnConnection for Addin: SearchWorkItems.Connect</description>
</entry>
Not sure if the error is significant or not.
Love to find out if anyone else has figured out this issue.