A couple of updates on Series 4 availability have come my way...
Brickset is reporting that Mueller Markt stores in Stuttgart and Winnenden, Germany are now getting Series 4 Collectible Minifigures. The reported price is €1.99 per pack.
Also via Brickset a commenter says Toys R Us in Graz, Austria has them in stock.
Finally there have been reports that Toys R Us in Virgina (US) are starting to see these rascally rascals too. The eastern seaboard has been fairly bare of pins on the Series 4 Rollout Map to date. This may be a sign they are starting to arrive.
More as it happens.