My take on the cherry advert (which, by the way, you can watch at
http://www.visit4info.com/details.cfm?adid=17894):
The mean girl, who keeps trying to scare off the other girl represents the other 4 major phone retailers, the girl with the cake and cherry represents the 3 mobile network.
One of the fruits of the network is music, which scares off the mean girl when she tries to eat it, but the second girl enjoys the music and then eats the cherry, showing that she can use and likes the service offered. The tagline "We like music" then becomes appropriate"