If you have a book to plug, and you live in the UK -- or even if you live elsewhere -- one site to keep an eye on is the UK publishers publicity circle (PPC). This, as its name suggests, is a group of professional publicists who meet together (in real life, face to face) on a monthly basis and have a discussion based on input from editors of magazines and the like who might be interested in featuring books.
The PPP web site is open to non-members and you can find quite a lot of useful information there. Usually, for instance, there is a summary of the information which was passed on at the last meeting; and there is an archive of such summaries.
In July the PPC discussed literary web sites, and if you go to the summary page you can find guidance on what the editors/bosses of half a dozen such sites might be interested in. Mostly, of course, they are looking for input from the big trade houses, and big names to interview or feature. However, clever publicity seekers who can work out an angle might well strike lucky.