Technical books, reference books, textbooks, cookbooks, and children's books tend to be a poor fit for dedicated e-readers.
E-readers are designed to handle narrative material that consists of a stream of words that you read from the beginning to the end. They don't much like illustrations, charts, graphs, pictures, maps, font changes, footnotes, endnotes, indexes, page references, etc. Which isn't to say you can't do these things, but it won't be convenient.
To answer your direct question, I would expect that B&N will be focusing more on filling out its fiction inventory, which it can mainly do by working with its current suppliers, than in negotiating contracts with the various independent publishers that produce most of the technical publications. Just my guess.
But my suggestion would be to consider whether there's really much value to you to having technical books on a small-screen e-reader.