According to Rob S. Conley's excellent blog, the Blackmarsh Setting is ready to be released through the Print on Demand company Lightning Source in about a week or so. Blackmoor fans will find many similarities between this setting and Arneson's world. The map for it was created through a process believed to be the same as what Arneson did when coming up with his map for Blackmoor. However, the author is quick to point out that:
"Blackmarsh is a homage to Dave Arneson's Blackmoor. But it is not a clone. The elements that it shares are; drawn from a map of holland, has a castle with a dungeon underneath where access is controlled by the elves, an elven forest, vikings roaming around, and there is a larger kingdom to the southeast. Beyond that background, the locales and details are unique to the Blackmarsh setting."
In additon to these elements, Blackmarsh also has the Mountain that Fell, a meteorite that fell from the sky, creating the Smoking Bay, a seeming parallell to the crashed spaceship of Blackmoor. Conley has previously suggested that the Blackmarsh Setting could be connected to his other projects of the Southlands (From the Points of Light) and the Wild North (published in Fight On #3), both also having some connection to Blackmoor.
With Code Monkey Press's Shaerdreath Setting and Dolmen Creative's Destiny6 game running into pre-production problems, could Blackmarsh be the first Arneson Tribute setting to actually get published? still, there is a fine line between homage and IP violation, and hopefully all involved in these projects will be careful.