When visiting a new city, it always amuses me to check out signs of all kinds. I think every city with any kind of self awareness have a graphical guideline that they use in their public communication. In a city as old as London, that signature have of course changed over the years, leaving a trail of different trends regarding how to communicate to the urbans.
I don´t know about you, but I think the old signs looked better. The don´t seem to be so sloppy when it comes down to kerning, and stuff like that.