We are experiencing this same issue. Before we get the 11708 error we get a few 1603 errors and before all those we get an entry saying the old version could be be uninstalled. The reason that the program cannot be uninstalled varies from machine to machine. The biggest issue we have is that SCCM is reporting that the install succeeded.
We have about 100 out of 600 machines with this issue. I tested one machine and found that the Uninstall of Adobe was broken. I had to run a MS Fixit to solve the problem,http://support.microsoft.com/mats/Program_Install_and_Uninstall/en-us.
We are hoping to find a better solution as we have another 2000 machines to deploy to and the false positive is a big issue. Tracking down which one reported correctly and which did not is a big hassle.
A beta tool for cleaning up uninstalls and permissions issues will appear on LABs in a few days. Try it out.
Whatever method you choose, check the logs and see if you can identify the problem file/registry entry and then script the needed change.
Any word on when the beta tool for cleaning up uninstalls will be released?