I don't know who's responsible, (does anyone else?), but well done whoever. I've seen loads of different 'Poems On The Underground" posters with spoofs of famous poems in a huge anti-Esso/Bush campaign.

Here's one I saw earlier:

SONNET 18 (apols to William Shakespeare)

Shall I compare thee to a multi-national?
Thou art more arrogant and polluting
Rough winds remind me to be rational
As global warming starts to put the boot in.
Sometimes too hot the burning sun doth shine
Thank Esso, and the president they paid
To ditch the Kyoto Treaty line by line
And break all the promises he'd made.
But Esso's market dominance will fade
As drivers turn their back on Esso fuel,
A mortal blow to this too dirty trade
Could bring about the end of Dubya's rule,
But so long as Esso struts with Bush in train,
So long will they continue this campaign.