The house was actually torn down and a new one has been constructed, so once Google updates SV the Tanner House will disappear.
Update: So it finally happened. Google updated the SV imagery, the Alf house is gone forever. I'll keep the map though, so people get an idea of where the house was located. The adress is/was: 708 Moreno Avenue, Brentwood, Los Angeles.
TV Locations, No Longer There, Buildings - Misc
Links: en.wikipedia.org
By: Xeba73
http://images.wikia.com/alf/images/e/e2/Tanner_House.png