When you want to handle a click in your life wallpaper you should use onCommand and wait for the action WallpaperManager.COMMAND_TAP. This is described e.g. in the discussion thread: Android Live Wallpaper Touch Event Hierarchy.
This works fine on my phone, but when i deploy the wallpaper to a tablet (in my case the motorola xoom with android 3.1) COMMAND_TAP is also triggered, when an icon on the home-screen is pressed.
I added a workaround by storing the visible state and delaying the onCommand handling by 1000ms, but I would like a real solution for this problem.