This is going to be AWESOME.
Publishers dedicate marketing and publicity staff to your book, with their biggest push focused around the launch. It's called "event marketing" in the industry.
What that means is that there's one big push, but no long term marketing strategy for the book...and this is where most authors (and some agents) get really grouchy. ("They're not doing anything anymore!")
But before we start Publisher bashing, as is so en vogue these days, consider that just as your book had some launch-time marketing (galleys printed, an ad somewhere, etc.) the next book on that publicist's list has to get the same attention. The publisher has to move on.
Which means that, at this stage, your own marketing efforts have to get more aggressive and your strategy more sophisticated. In post one, we talked about building the foundation of your online presence. On Tuesday, about focusing your online strategy. At this stage, you should focus on marrying your marketing foundation (blog, Twitter, Facebook, etc.) with specific marketing strategy.
This means getting creative. Your goal should be to keep your book(s) on people's minds in the online space, where attention spans are notoriously short.
This is not done by "selling" your book.
As you've no doubt heard before, broadcasting "BUY MY BOOK" is a quick way to get ignored. Create value for your audience--by being funny, like Maureen Johnson, finding interesting images on Flickr, or marrying your writing interests with something broader, as Sarah Fine does with psychology and YA literature.
Keep them coming back for your digital content and persona (separate from your book) and they'll get your book news (new releases, discounted ebooks, etc.) too. Organically piqued interest has a much greater chance of generating sales and word-of-mouth advertising.
Yes, this "online stuff" takes time. Or money (you can certainly pay some very talented professionals to do this for you). The online space has become a hugely important marketing and sales environment. If you choose to ignore that online space, you risk dooming your book to the "Launch and Fizzle" pattern so many books fall into.