Diff 1857 is close enough to the ATH to probably not enter truly uncharted territory.
What about the proposal of weekly/monthly superblocks of ever-increasing difficulty?
I'm leaning towards a 30min block once a week. With current difficulty this would get us slightly above world record. If difficulty increases, the goal of the weekly superblock would increase too, going farther where no man has gone before.
If it's not poloniex nor mintpal my guess is that it's btc38, but how could we really know?
Almost 50% of the network is on 0.8.x versions though, according to the sample seen by the explorer, they would have to update, that can be seen as both a bad or a good thing.
I'd give a couple of weeks for everyone to update and use the built-in alert system to let everyone know.
I hate it that we still have one pool dominating, however it does make hard-forking easier and I'm thankful that it's ypool because it's behaving really well.