Ringer Mattforce spotted the following post over on the IGN boards following the posting of these screencaps.

Southfarthing Pipeweed! Treebeard Prowls Isengard

The post (corrected for appalling grammer) reads:

At the end. After all the orcs are washed away. At Isengard. Pippin and merry are looking for food. and Pippin finds an apple floating in the water. and they follow the apples.

And they get to this little like store room where Isengard had all its food. like chicken and fruits and all. And then Pippin sees a barrel that says “South Farthing” and they open up the barrel and its full of weed from the Shire!

And at one point Pippin’s like “Do you think we should give Treebeard some of this?” And Merry’s like “No, it’s dead plant, he wouldn’t understand, it could be one of his relatives”. And they both start smoking it. And start laughing their asses off. And smoke comes out of the room, they fog machined it! And Treebeard’s looking at the smoke coming out of the doorway and listening to Merry and Pippin laugh their asses off!!!

This tends to mesh with War of the Ring’s description: “After the trashing of Isengard, Merry and Pippin mock Saruman. Floating apples, and other food lead them to discover the storeroom where they promptly find two barrels of Long Bottom Leaf. (One barrel for each of them of course!)”

Not long to wait to find out, now.