a real world point of view
Doctor Who Storybooks were annual, hardbound Panini books that began publication in 2007. They were the brainchild of Clayton Hickman, who created the line as a response to BBC Worldwide's revocation of Panini's right to release a book branded "the Doctor Who annual". Panini had proven with their Doctor Who Annual 2006 there was a market for Doctor Who annuals about the BBC Wales version of the show. Soon after the successful relaunch of the Doctor Who annual, Worldwide pulled Panini's rights to use the title "Doctor Who Annual", giving the "Annual" brand to BBC Books. Nevertheless, they allowed Panini to create an "annual-like" publication.
Thus, from 2007-2010 there were two annually-published Doctor Who books in the United Kingdom. The "Official Annual" series was printed by BBC Books and tended to be aimed at a young audience, much like the old World Distributors annuals. These books had a greater emphasis on "activities", much like their predecessors from the 20th century.
The Storybooks built on the formula seen in Panini's Doctor Who Annual 2006. Aimed at a slightly older crowd, each volume was mostly comprised of short narratives and comic strips — or, as the title implied, stories. These stories were written by people who had written for the television series or other licensed ranges arising from the BBC Wales series. Writers like Russell T Davies, Robert Shearman, Gareth Roberts, Mark Gatiss, Tom MacRae and Steven Moffat all contributed to the Storybooks.
The future of the publication was thrown in doubt when DWM 426 announced that the planned 2011 edition was cancelled due to "licensing issues". As of late 2011, it appeared there would be no 2012 edition either, meaning that the Storybook may ultimately become a phenomenon unique to the Tenth Doctor's era. The series was replaced by a new annual series entitled The Brilliant Book, which started in 2011 and was published by BBC Books.