Data.Graph vs. FGL

I'm doing a little cleanup on FGL (http://web.engr.oregonstate.edu/~erwig/fgl/haskell/). Part of that includes renaming modules to fit the hierarchical scheme; my plan was to call the base Data.Graph. Lo and behold, however, Data.Graph already exists! Could someone enlighten me on the reason what is now Data.Graph was chosen over FGL for inclusion into the base library? Also, given that Data.Graph already exists, what would be a good place for FGL? Data.Graph.FGL seems iffy for two reasons - it implies that it's a subset of Data.Graph, and it still uses an acronym instead of a descriptive name. Thanks much! Abe