Updated: Sony and Barnes & Noble may be launching two of the most high-profile challengers to Amazon’s Kindle, but supply chain challenges could keep both companies from denting Kindle’s popularity this holiday season. (Then again, Amazon (NSDQ: AMZN) had its own problems shipping Kindles over the holidays last year).

Sony (NYSE: SNE) started pre-selling its new devices—including the Daily Edition, its first with WIFI—this week on Sony Style, its in-house e-commerce site. But demand that “exceeded expectations” could keep buyers from getting them in time for the holiday, according to the NYT and others. The company says it expects to ship the Daily Edition Readers from Dec. 18 through Jan 8, but can’t guarantee delivery dates.

Meanwhile, Barnes & Noble (NYSE: BKS) has pushed back the delivery dates for late buyers of its Nook e-reader and now says it is sold out through the holidays. The company first said Nooks would be available in some stores on Nov. 30, with online buyers getting the same shipping date. Now, B&N expects to ship the first online orders on Dec. 11, with later ones shipping Dec. 18—though it told the WSJ that it still expects the latest shipments to arrive by Christmas. Friday, the chain admitted to NYT’s Bits” that it has completely sold out of the Nook. All new orders will be delivered starting the week of Jan. 4.

In contrast, Amazon—with its two holiday seasons worth of experience—tells the Journal the Kindle “remains in stock” and is ready for “immediate shipment.”

Staci adds: The other wireless e-reader due this season, the IREX, was supposed to be in Best Buy stores in October or early this month—the shelf space has been set aside for weeks—but has yet to make an appearance. No comment or explanation yet from the company despite repeated requests.

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