What has the font to do with you knowing whether or not you are connected to wireless?
I just disabled the WiFi symbol all together, in all actuality I don't need it. Anything I do will pretty much instantly let me know I'm not connected to a network anyway.
That and the bluetooth symbol as well as time machine and airplay on machines that I'm not going to airplay from.
also, once you know that if you are not connected to wifi the symbol will be grey, when you are connected the symbol is black then the thin font doesn't matter anymore. It's just different than what we are used to seeing.