For those you who've upgraded to dual-layer burners, Verbatim DL media has been showing up at some Best Buy stores packaged with 8 single layer 8x DVD+R discs and 1 4x DVD+RW discs for a total price of $29.90 in what Verbatim calls "double layer solution kit".
Regular packs of +DL media are still not available.
On a related note, those of you with Sony DRU-700A burners (like me) might be interested to know that the drive is actually a LiteOn SOHW-832S OEM. You can make the drive regionless without flashing the firmware using the LtnRPC tool available here...
Good info to know. Maybe I should take mine out of the box.