Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Barnes & Noble (NYSE: BKS) popped 10% in intraday trading today after Staples (Nasdaq: SPLS) announced plans to sell its e-reader.

So what: Office supply retailer Staples will start selling Barnes & Noble's Nook Color Android-based e-book reader on May 1 in its stores and online for $249. Staples is the world's largest office products company and the second largest e-commerce retailer, with annual sales of $25 billion and 90,000 associates in 26 countries.

Now what: B&N has only 705 bookstores and 636 college bookstores in the U.S., so the Staples relationship should expand availability of the Nook. That said, the Nook is already available at Best Buy, Amazon, and of course, B&N. It is hard to believe the incremental distribution from the Staples relationship will overcome the challenges of the bricks-and-mortar bookseller business.

Interested in more info on Barnes & Noble? Add it to your watchlist by clicking here.

Fool contributor Cindy Johnson does not own shares of any company named above. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.