It's enough of a non-issue for Apple to consider turning ECN on by default in their next OS releases. The subsequent sharp uptick in ECN traffic (since there's a lot of Apple devices out there) should help to eliminate the rest.

It's also enough of a non-issue for me personally to turn ECN on by default on all my machines. Of course, I get particular benefit from doing so since I usually have cake running at my bottleneck.

- Jonathan Morton