I wasn't privy to any actual sales data when I worked at Amazon, but anecdotally it seemed that while there was a real, reasonable bump on "Cyber Monday", Black

I wasn't privy to any actual sales data when I worked at Amazon, but anecdotally it seemed that while there was a real, reasonable bump on "Cyber Monday", Black Friday itself was huge (it probably helped that we had Black Friday sales!) and so was Thanksgiving Day (when I guess families would talk about all the shopping they would do the next day when stores were open and take out their laptops to try and get an early start)