This is very bad news. Now, the only options are:
1) Rockstar challenges the rating, hoping for an upgrade to Mature
2) Rockstar lessens the blood and gore in the game in order to get a Mature rating
3) Game is released as is, and is severly limited to which stores it appears in
All three options are terrible, with #3 being the best for us (anyone can get an "AO" game online if they try hard enough). Looks like anyone under 18 is gonna have to rethink getting this game.