The story may be exactly as it's being portrayed below, internal politics, but it makes one wonder if perhaps Surkov was unwilling to participate or create the PR (ie, propaganda) that will be necessary if Russia agrees to No Fly Zones over parts of Syria.
I admit this may be a stretch, but it is interesting timing...
2013.5.8 'Grey Cardinal' Surkov Leaves Halls Of Power In Wake Of Putin Criticism (RT, youtube.com):
President Vladimir Putin has signed the voluntary resignation of deputy PM Vladislav Surkov, best known as the architect of Russia's current political system - the 'sovereign democracy.'
2013.5.8 Jumped Or Pushed?, Russia's Deputy PM Surkov 'Resigns' (Euronews, youtube.com):
Russian deputy prime minister Vladislav Surkov has stepped down - a move many are reading as Surkov being forced out.
A statement released by the Kremlin says Surkov, 48, had his resignation accepted by President Vladimir Putin.
The move comes just one day after a meeting during which Putin scolded the government for not carrying out his orders.
Surkov joined the government in 1999 and previously served as first deputy Kremlin chief of staff, before being demoted in December 2011.
Surkov is seen as having been the administration's ideologue. He created the concept of "sovereign democracy" - which effectively sidelined all opposition that was not controlled by the Kremlin.
An ally of former president Dmitry Medvedev, Surkov's departure may reveal a rift between Medvedev and Putin.
Putin has denied Surkov's departure is linked to a probe by Russian investigators into the Skolkovo hi-tech fund, whose executives are accused of stealing close to 570,000 euros. Skolkovo was created by Medvedev and Surkov sits on the supervisory board.