Changing The Oil Too Often

http://www.latimes.com/business/la-fi-autos-oil-change-20111215,0,4554184.story
Toyota still recommends 5000 miles unless it's changed from '09...

BMW and many others change every 7,500 miles, as does my KIA Forte. Engines are so much cleaner today, little combustion residuals get to the oil, so the oil lasts a lot longer. If all the driving is short trips, in town, without complete warm up being achieved, then it will require more frequent changes.
I change every 7,500 miles now, but I do monitor the oils condition every 1,000 miles to check for cleanliness and dilution from fuel.