Here is my PC specs:

AMD Phenom II 965 Black Edition
MSI 790FX-GD70
8GB Super Talent DDR3 1600MHz
2TB Western Digital Caviar Green SATA II
350GB Samsung SATA II
ATI Radeon HD 5450
ASUS Xonar D2X
Sony/Nec Optiarc DVD-RW SATA II.

A few lines before the "still waiting for root device", it writes something like that: "couldn't alloc IOUSBMassStorageClass". Maybe it's this kext?