Wow, that's exactly what i thought upon first listen.
Definitely hearing some closeness to Pirates music in there.
I think it must be the 3/4 timing. It gives it a faster, beatier feel.
(Absolutely LOVE that Coldplay have finally used 3/4 timing!)
Didn't Chris say in an interview that is was about Witch hangings and how scary it was that people were just getting hanged out of fear? I really seem to remember that, so I picture Witches in London especially during these lines:
At night they would go walking
‘Til the breaking of the day,
So we rode down to the river
Where Victorian ghosts pray
For their curses to be broken
We go underneath the arches
Where the witches are and they say
There are ghost towns in the ocean
I would agree with the Western sound. There is a PS2 game called Darkwatch that this song immediately put in my mind. The game is a 1st person shooter where you are a gunfighter/newly made vampire in a Gothic Western scenario . The gunslinger has to battle his way through graveyards and ghost-towns, fighting skeletons, undead riders, banshees, etc. The game is perhaps too violent for some, but my son and I used to enjoy it. After listening to "Cemeteries" we immediately dusted it off and played it for a few hours.
On a side note, you don't know how special it is for me to be able to bond with my 14-year-old son over things like the music of Coldplay.