There is a hard push from part of the community to use an active rules set. Most of these people did not experience the 4th Ed D&D debacle or GW's attempts to kill Bloodbowl, so they think its impossible to continue with an old rules edition. While 8th would ordinarily be completely stagnant, there is a unified WHF tournament scene in the US that could do small yearly changes to keep things fresh that would be trusted well enough by most. There are some hard core fanbois who want to bury it and make everyone jump to Age of Shitmar, however, that are forcing the issue. I personally am burnt out on skirmish games (and the community for them is full of asshats), so anything I continue with has to be regimented. Our local league is continuing with 8th for now, but most of the SoCal scene are leaning towards Kings of War. The south, especially Texas, looks like its migrating en masse towards KoW as well. So far the pro AoS camp has not been able to even remotely come up with something workable that doesn't completely rewrite the entire rules (which leads to more infighting) and there has yet to be a single AoS event announced, at least within the Masters community. Several Kings of War events have gone up, though, and most events on the calendar are continuing to use 8th until the Masters in February at the Las Vegas Open.
Of course Reese Robins, who runs the open that is hosting the Masters Finals, decided to put his event the same weekend as the Superbowl..... yeah that's going to go great.....