it seems if you type "android" at the same command prompt you type your cordova commands, you get a separate Android SDK manager then the one launched via Eclipse and so then there you select the appropriate packages and updates to achieve the version number of the Adroid SDK required. For me I'm guessing it's from an adt-bundle I installed with _? (I don't know actually no clue) that runs instead.
My best guess is the installer when updating doesn't doesn't update the path correctly.
Ya you need to manually correct duplicates and anomalies in the path.
Point to the "sdk" folder and tools of a valid most current adt-bundle-windows folder.
Maybe it was NetBeans that did this?
No it seems plausible when I put an update of Eclipse (C:\Library\Dev\Android\adt-bundle-windows-*) I must have not realized I needed to update the path too having done it manually the first time to get it to work.
It seems I needed plateform-tools added as well for adb to run the emulate command...
C:\Library\Dev\Android\adt-bundle-windows-x86_64-20131030\sdk;C:\Library\Dev\Android\adt-bundle-windows-x86_64-20131030\sdk\tools;C:\Library\Dev\Android\adt-bundle-windows-x86_64-20131030\sdk\platform-tools;