on LMDE you can't just add the PPA and make it work. thats for Ubuntu or Linux Mint 13 Maya, NOT Debian.
Note: LMDE = Linux Mint DEBIAN Edition
if you want easy Bumblebee, install Linux Mint 13 Maya, then install by PPA.
on Debian OS, the following is easy and guaranteed to keep you cool:
***This will work on Debian***
Disable NVIDIA in Optimus and run Integrated Intel graphics only:http://main.solusos.com/showthread.php? ... Priority-1
Mint 14 Cinnamon 64-bit | SolusOS
1.2 64-bit | SolusOS
Dell Inspiron 15R(N5110) - Intel i7-2670QM, 4GB DDR3 1333Mhz, Intel 6 Express Chipset HM67
NVIDIA GeForce GT 525M, 500GB SATA, 15.6" HD 1366x768 - nVidia Optimus Graphics
powered by Bumblebee