Well while it is not a complete campaign, it is close...
Levels 1 to 10, Two Books, Cold Equation followed by The Ragged Edge in the B5 series, I hope they continue it with another book from 11 to 20, but as B5 ends at level 20 I'm sure its campaigns will be planned for up to 10th level most of the time...
I too liked the complete campaign concept, Wizards of the Coast are now starting to do this with their "Expedition" series of books which I'm sorry to say are better formatted (at least Expedition to Castle Ravenloft).
There is a lot of potential in the series, even if they concentrate on settings or make them general.
I for one would like to see a campaign storyline which includes their other d20 products.
A story that incorporates the Cities of Fantasy, with the Slayers Guides examples, and has characters built from their Quintessential and Encyclopeadia series and maybe even the planes series as well.
That and maybe including some of the characters from the storylines they have running through those books.
It would be something I would buy