Double post. Sorry.

i hear definitely no bb30. possibly bb386 (bb30 related) in the future.
aftermarket chainrings? nope. i think somewhere mentioned 4-bolt crank arms. i dont know if it means a hidden fifth bolt or 4-bolt like the mtb cranks. besides, aftermarket chainring makers are relatively flexible, and adapt to whatever shimano does. shimano is certainly not going to bother doing anything with the aftermarket chainring makers in mind. i wouldnt either.
smoother shifting- i hear it's coming. some sort of proprietary shift cable. i dont know if it's super thin, at some point a thinner wire digs into the plastic liner easier, thus increasing friction. so maybe also a new, stiffer liner, kept flexible by being drawn thinner. and maybe a new lubricant that resembles micro caviar, and the cable rolls on the "eggs".
everything past the proprietary shift cable is my pure speculation...

personally i don´t think neither campagnolo, sram or shimano would put out something that isn´t durable and would hold up for much