Edited OP to ask that only actively used abbreviations be listed here.
This is why I would pay attention to the usage of "GG" after the release of GS to see if it has staying power. It might only be used for the prerelease of chapter 5 and then never again. OTOH, (heh I used another acronym) "Grey Cloak" was used within the first few chapters of WN, and percisted through the book until he was named in the final battle.
EBG might fall into one of the slightly obscure ones, but I know it's turned me for a loop a few times (which might be explained by it's obscurity). I'm concerned that the dresden files section is getting very crouded, which is partially why I suggested that you break out the acronyms for the works out into their own section. You might also consider making a section for "Obscure DF character abreviations" For toons that showed up in one book and were gone like EBG.
Oh, I'm pretty sure I've seen HHWB's boss, as named in BR abreviated... isn't he, Lord of Slowest Terror? Hmmm pretty sure I never had a mental double take at "LOST" though...
