No, Apple is NOT using standard DDR3 RAM sticks. The RAM is soldered to the board in 256MB packages.
Hate to quote my own post but pictures are obvious:
https://forums.macrumors.com/threads/593227/
Actually, there's more DIMM chips unside. Furthermore:
They're using standard, Hynix (at least for me) 128MB chips. The only "non-standard" about it, is that its soldered onto the logic board instead of a memory board.
Edit: Here's a picture from ifixit, it shows a Rev. A but it has the same concept.