It's the reason the PC platform is the lead platform

I'm obviously spending way more time on this than it's probably worth, though curoisty always gets me on these things.
I'm curious what your take on these articles are, In terms of Digital download versus box sets.
If I am reading This correctly, it seems to me, Steam sold 1.6 Million copies of CoD:Black Ops. for 2010
Again, assuming VGchartz is semi accurate, then it looks like retail sales of CoD:Black ops was around 1 Million for the first 10 weeks, which is basically Nov-Dec of 2010,so I believe it's pretty close
So maybe 2-1 DD to retail ? Is steam the only DD option for Blops ?
Looking at the PS3 sales numbers for Lifetime, it's 9 million copies. Hard to believe the PC with DD matched those numbers. Note, I'm not Pro console or Anti DD. Just looking for the facts, wherever they are hidden.