Wow, that is amazingly ugly. Colorizing the current Airport logo might be nice, but the black background of this makes it nearly unreadable, and the shape isn't as pleasing as the default one either. Certainly not usable at a glance.
And what is with the trend of people posting icon makeovers like this? At the very least post it as a patch to the original Airport menu extra, and perform some integrity checks. Distributing a copy of the whole extra is going to cause inevitable version mismatches and breakage. I can't wait until people screw up their Leopard installations with crap like this in a couple months...
This goes for all other programs that see fit to wholesale replace things they have no business replacing, including other "color menu extras" offerings, and Aqua4iTunes.