Yes, i believe it WAS shot @ Whiteman Airport (WHP). Noticed just today that someone had posted some still photo shots of the episode while filming there back in 1968 at the airport.
Of course, all the stills don't show the eventual build-up of industry and businesses that are now lining up and down San Fernando Rd.
Someone has made mention of the "smokestacks" in the background.
Those are the "4-stacks" that pilots and controllers mention as a landmark around the airport area. (the 'four stacks' also are mentioned in the Sandra Bullock movie "the Net" - in which a friend of hers flies his Cessna airplane into the stacks after being 'off-course', due to a malfunction - which the audience is asked to believe can be done via computer. (it can't).
The four stacks (there are really six now), are just south of Whiteman Airport.
i've posted a copy of the Aunt Bee photo page here:
http://www.flickr.com/photos/eyeinthelasky/2490781172/