Everyone is right.
Buying this album was one of the best decisions I've ever made in my life. For the money, I've never had anything blow my mind quite like this album. It's obvious. Buy it now.

The all time punk "classic"
London Calling should be in any music lovers collection. I hesitate to call it classic because it is so fresh after 20+ years that is seems inappropriate to tag it that way. Much the way that Sgt Pepper or Nevermind feels unique and current no matter when you encounter it 1970, 1994 or 2008

Perfection in the punk genre and beyond
The song "London Calling" touched a nerve at the start of the 1980s. Like the Young Ones, 2000AD, and the impact of new wave was being felt. The haze of the seventies was gone. A new dawn of nihilism was upon us (attack commercial greed - Koka Kola) people were scared and we were taught in schools of nuclear holocausts (London Calling) but the beauty and naivety still remains in songs such as "Train in Vain". As strong as The Stones Exile on Main St (the great double album of several years earlier) but preaching to an audience who would rather die than associate themselves with such a 60s / 70s iconic group. This was the music of our generation and we embraced it will both arms. Nothing would be the same again, and The Clash had moved New Wave to the next step, a kind of wary respectability.

Great Album
I was torn between 4 and 5 stars and would have done 4 1/2 if I knew how. I was probably a little bit harsher in my rating because of the record's reputation. It probably won't disappoint you, but I don't think it approaches the best album ever. It very likely has some great songs you've never heard, though, and some favorite ones familiar to you. It was ahead of its time with all the different styles melding together nicely, but there are some weak points in my opinion. But still better than 90% of other good albums out there, and better than 98% of all the crap you can get.

Nothing else comes close
Not only is London Calling one of the best-written albums ever, it's one of the best-sounding albums as well. London Calling is an auditory delight, thanks in a large part due to Guy Stevens' impeccable production. The music is rich and mellifluous, with each song drifting through various genres and musical styles without ever becoming uneven or overwhelming. There are no weak tracks here, just great songs and greater songs. London Calling is a landmark rock album, and is essential for anyone who likes classic rock, punk, alternative, reggae, or great music in general.