Tire rotation - absolutely necessary?

Curious. How many miles did you get verus the mileage rating of the tires? I guess that would be a two part answer. How many miles on the two front tires and then the two rear tires?

 

I usually keep the front tyres 3-5 psi above recommended pressures and leave them on the front until they wear to 3mm tread depth. The extra psi evens out the wear pattern somewhat. I then renew the fronts and bearing in mind that a) tyres need to bed in for up 500 miles to remove all traces of the mould release chemicals that are present on new tyres and b) it is recommended that the grippiest tyres go on the rear, I leave them on the front for 500 miles then swap fronts to back and repeat this process when the older tyres, now on the front, wear out (FWD cars).
Another consideration for those who don't rotate and don't do high mileages is the tyre age. Most tyres start to show sign of age and/or UV radiation damage from the sun, i.e. cracks on the edge of the sidewall, at or before 5 years old. So it pays to use them up before this happens.