Competition is heating up in the electronic book reader world, but now Sony is warning customers that demand for its new product may exceed holiday supply.

According to the Wall Street Journal, "a Sony Web site now states that pre-orders will ship Dec. 18 through Jan. 8, and the actual delivery date cannot be guaranteed."

The Sony Daily Edition Reader, retailing for $399, is competing with the Kindle from Amazon.com and the Nook from Barnes and Noble.

Read the story here.