While trying out the ESRI sample Bing map app. I came across the problem that the ESRI.ArcGIS.Client dll does not contain the Projection namespace (ESRI.ArcGIS.Client.Projection). I am using ESRI 2.0 API. Is anyone having this problem?
Solved my issue. Even though I installed the latest build (314), the updates/changes to the ESRI API wont be installed unless you first uninstall the last build.