I've just noticed that buses have <colour> line on them instead of / as well as numbers - is this new? And does it serve any purpose apart from making them look like knock off London underground wannabes?

As far as I know the line colours have no purpose.

I'd like to see if the red line lives up to its name.

the different coloured lines are different routes i'm led to beleive! like the supertram maps have different coloured routes!