See forum post below:
http://forum.pmease.com/viewtopic.php?f=1&t=2644

Thanks. I did that and I can see the command that calculates the latest rev. Strange. My TFS repo config is configured with 6 different source folders to checkout. I have made a code change in 1 of those folders. When looking at the server log, it is executing the history command on each of the different source folders EXCEPT for the one that contains my new code change. If I manually run the same history command on the command line against the directory that contains my code change, it properly reports the new revision. So if QB would not skip that specific directory, I am sure it would detect a new revision and trigger a build. So the question is why is that one source directory being skipped during the detection phase of the build?

I tried changing the order of the 6 different source folders, but that didn't work.
I verified that the tf workspace definition contained all 6 source folders, and it does.
I verified that when I force a build in QB, all 6 source folders are being checked out.

Here is the list of my source folders in my repo definition:
${vars.getValue("serverSourceDir")}/Applications/ActivityTracker/RigInfoMobile.Common
${vars.getValue("serverSourceDir")}/Common/Android/Libraries/ArcGIS
${vars.getValue("serverSourceDir")}/Common/Android/Libraries/ArcGISLite
${vars.getValue("serverSourceDir")}/ThirdParty/Android
${vars.getValue("serverSourceDir")}/Applications/ActivityTracker/RigInfoMobile.Droid
${vars.getValue("serverSourceDir")}/Applications/ActivityTracker/RigInfoMobile.sln

You will notice that the directory that is being skipped (ArcGISLite) is very similar to another source directory (ArcGIS). Perhaps there is some string comparison bug inside QB??

Further information:

I just made a commit to one of the source folders that is NOT skipped, and it did properly trigger a new build. However, the list of SCM changes as viewed from the QB web ui only lists the commit I made to the source folder that is NOT skipped. It does not show the original commit to the source folder that is skipped. However, that change IS inside the build as it is still properly checking out all 6 folders. It just doesn't do the change detection on it.