There was a warranty extension for this 8 years/80k. You might find this interesting from automotiveforums.com:
It is a design flaw in the V6 EGR ports caused by the port being to small and the metal it is made from actually attracting carbon buildup. The reason it wasn't an actual recall was because it isn't a safety concern, and it doesn't happen to all cars. Using higher octane fuel and babying the car contribute heavily to the speed at which problems develop. It is a much more common occurence in Odyssey vans because they tend to be driven more gently. I've seen the EGR kit done on vans with 20,000 miles on them.
As far as doing it yourself, if your car is out of the emmissions extension warranty, 8 years/80,000 miles. Spend the $350-$400 dollars to have the dealership do it. The pipe they install after drilling out the EGR port is the most important part because it's made from a different metal that the carbon doesn't collect on.