I tried to generate an Android build of a test project, and it gave me this error:
"Android SDK is missing required platform api
Minimum platform required is Android 4.0 (API level 14)"
I then used the "Update SDK" button it gave, and it went into an infinite loop of "Updating Android SDK" and "Detecting installed platforms".
I canceled it, downloaded the latest official Android SDK, and selected and installed all of the SDKs from 4.0/14 and up. But Unity is still fails to detect it, tries to update and goed back into the endless "Updating/Detecting/Updating/Detecting/etc" loop.