I am certainly no expert, but my very trusted independent mechanic (who is retired, picky on whose cars he will work on, often gives me advice for free, and helps me troubleshoot over the phone to save me money) recommends changes every 5,000 miles (dino) for two reasons:
1) it is easy to remember and good for the engine
2) it gives he and I an opportunity to go over the car on a regular basis and check overall condition. I do some of my own oil changes, and "getting under the hood" is a good thing.

He admits it may be overkill, but claims that if I maintain this schedule these engines will last a long time.

My 560sec which has been maintained this way for the last 100,000 miles now has 165,000 miles and the camshaft lobes look new.
My '93 turbo with 145,000 miles has been maintained this way for the last 75,000 miles and also runs like new.

It may be too often, and once and a while I slip a bit, but I have two very strong running cars that I cherish and would like to keep for another 100,000 miles!
John

John

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John Gillespie
1988 560sec - 192k miles
2006 CLK500 - 40K miles
1995 E300 - 202k miles