It means the marketing department is taking your book seriously. Consider an Agent Articles about writing often address the topic of how to get an agent, and the difficulty of getting an agent when you have not yet written a book. In this case, I had written some articles for computer magazines. An agent read one, liked it, and contacted me via email. As you should do with any unknown agent, I checked a book of literary agents, then decided to give book writing a try.
Agents are good at negotiating book contracts.
Here I am speaking of the positives of having an agent, but in computer publishing it is very possible to approach the publisher directly. Many computer publishers are eager accept proposals directly from authors. Look through the computer section of Writer's Market and read their guidelines. I thought that writing a computer book would be exciting, and it was, but the truth is sometimes I had to drag myself down into the basement after a day's work and putting the children to bed. It is common for a writer to become occasionally bogged down with their writing, but in the computer book field it is made worse because of the fairly tight schedule some computer books are produced under.