I wasn’t sure if this went here or GQ or even IMHO…how come new books and DVD’s and CD’s are released on Tuesday? Why Tuesday?
This is just a WAG, but bear with me:
When I was working for a radio station, we learned the´hard way not to implement anything on a mMonday. The weekend tends to screw things up and the company didn’t wan to pay OT for people to come in on a Sunday to fix last minute glitches.
Applying this train of thought to your question, my guess is that Tuesday is a good day for marketing purposes. Not knowing how things work exactly in the US nowadays, I’d venture that a lot of ads for supermarkets/food fall on Thursdays/Fridays, since many poeple tend to shop for the weekend late in the week. Car ads would run over the weekend, when people are off work and have time to go shopping for a new car. Same goes for home improvement stuff and furniture.
However, beginning of the week might be a point where rates are lower. Also, splurging and buying the Indiana Jones DVD box might take more convincing than picking up a couple of steaks and a bottle of red for the weekend.
So, releasing in the beginning of the week is good, but Mondays are bad. What if something screws up with the delivery? You want to have the full staff on hand to unpack the latest shipments and get the displays up at Best Buy or Wal*Mart, whereas the weekend staff just re-stocks the shelfs and handle sales.
Of course, after this too long WAG, someone with the real and much easier reason is bound to show up. 
I assume this is America. DVDs and CDs are released on Mondays in the UK. Not sure about books, but I think its the same release day.
Start your week with a new release! IMO