CPU-Z says this:
PC3-10700 (667 MHz)
I am supposed to have PC3-10600 1333MHz.
What am I not understanding?
Or, is my RAM only half of what the label and seller claims it to be?
You do indeed have PC3-10600. CPU-Z shows only the half of it because DDR RAM like the names says - Double Data Rate - can transfer twice as much data on one I/O bus clock, than the actual IO frequency which CPUZ shows.
If you want to dig deeper in this topic check this link, it describes it really well.