For the upcoming tournament Euro 2008, Adidas and Puma have introduced new shirt numbers. Some examples can be seen on www.footballshirtculture.com.
For the Dutch team Nike has slightly adapted the toilet paper numbers. The diagonal strokes have been removed and the horizontal stroke on top of 6 and bottom of 9 are chopped of. They almost look like the basic constructed figures that I have drawn a while ago for a lecture about shirt numbers. I used this drawing to demonstrate that they are not suited to be used as shirt numbers. Obviously Nike has a different opinion - and a bad taste.
In the printing industry there has longtime been a rule of thumb for people who didn't understand typography: 'When in doubt, use Caslon'. William Caslon lived from 1692 till 1766, so he has never seen a football match. But his figures are legible and elegant, and far better than all the so-called modern designs that are introduced on football jerseys. 'When in doubt, use Caslon' should become a rule of thumb for desperate football teams and designers without typographic interest.
Figures from Walker by Matthew Carter
Figures based on two rectangles
Figures from Caslon semibold