The recently leaked and rather controversial Bones animator list has been disowned by Bones as not being an internal company document, however as Moon Phase rightly points out, they have not touched upon the genuineness of the information contained within (the personal details are thought to be genuine), nor shed any light on the provenance of the document.
Contained within the document is reference to an title by the name of 鋼の錬金術師 原作版 仮 / Hagane no Renkinjutsushi Original Work Version (provisional). Might this be an as yet unannounced FMA project? Unfortunately there seems to be too little information to say at this stage.
It may not be able to exceed the level of promising rumour until the veracity of the file is ascertained, but it is certainly an interesting proposition, and one which might make a lot of sense if it were to take the form of a manga based version (since currently the franchise is unexploitable because of the anime version having closed off the story, whilst the manga continues to go strong).