When I listen to the lyrics of this song, I kind of get the sense that Coldplay is speaking about television, hence the title "Life in Technicolor." Just turn on your TV and watch as the news reports the world as a "violent" one, "wars coming", every night "street lights glowing and sirens" (ambulances and cop cars) etc. The speaker of this song seems to understand that there exists such a world but he also recognizes that it's just a world/life in technicolor. It's a world behind a screen saturated with glamour (I use this in the original meaning of the word) and violence. Instead of feeding into this life in technicolor, the speaker seems to realize that though there's so much speak of "the end of the world", he accepts love as a powerful and motivating source. "Love don't let me go."
Anyway, I got the sense that's what the meaning of this song is about from the music video as well. Visually we see a group of parents and children around a puppet show watching this spectacular puppet show in utter awe. Is there a correlation with those people watching this puppet show and us watching our television sets?