"The Best Buys, the Staples, the PC Connections, they all still have a decent Mac software business," said Stephen Baker of retail research firm NPD Group. "This will have an impact on all those guys. [The release of an OS upgrade] is always a good opportunity for them to connect to customers, get them into the store and thinking about upgrading their devices."

And with Apple pushing Lion only through its download Mac App Store, those retailers will be out of luck this time around.

Likely forever, said Baker.

"The software business is in the throes of significant changes, and [Apple's move] is a part of that," said Baker. "The whole business is clearly changing how operating system developers deliver upgrades."

On Monday, Apple announced that it would some time next month for $29.99.