biosdevname in fedora 15 - why is this inconsistency?

[Petrus de Calguarium]

Tom Hughes wrote:

> Did you upgrade this machine from an earlier version of Fedora? If so
> then I suspect the old names will stick because you will have udev
> persistent naming rules for them.

No, I did a clean install. I installed a week before the first Test 
Candidate for the first Release Candidate of the Alpha for Fedora 15 
came out.
> 
> Check /etc/udev/rules.d/70-persistent-net.rules and I bet you have 
rules
> that are forcing the ethX names.

Yes, this file is present.