I'm sure I could push it to much closer to 20,000 miles but my goal is simply to be able to go about six months between changes. If you look at the dates of the samples you'll notice that the Sequoia gets a ton of miles put on it. It already over 500 miles since the oil change last Friday and we really didn't go anywhere. I'd be changing the oil every 4-6 weeks if I didn't go past the wasteful 3,000 mile old standard.
New Rule of Thumb:
5,000 miles with any name brand conventional
7,500 miles with any synthetic.