I don;t see how Coldplay can be compared to U2 for a couple of reasons.....
1)
U2 released their first 5 records in +- 7 years
Coldplay has released 2 albums plus the new one in 5 years...give it 3 years for the next one so 4 records in 8 years.
2)
Bono vs Chris Martin (songwriter)
at the age of 26 bono has penned down boy, october, war, uf, the joshua tree....if you look at the classics of those albums: i will follow, unforgettable fire, sbs, new yearsday, pride, bad, streets, with or without, still haven't found it's unbelievable...and those are classics for the non diehards...
Coldplay classics up till this point: yellow, in my place, clocks, trouble...a very mediocre speed of light is not a instant classic like in my place which when I first heared it struck me like a lightningstorm(very impressive first single)