Alolan Grimer looks interesting. It sort of looks like nuclear waste.
On another note, Serebii seems to have received information from the source who posted this Corocoro page that suggest that Type:Null has an evolution called Shiruvadi that has the ability called AR System that allows it to change its type depending on the item it is holding, much like Arceus' ability, Multitype, and that Jangmo-o's full evolution line is revealed with it being like this:
Jangmo-o > Jarango > Jararanga
It's evolutions will also be our first ever Dragon/Fighting types, which is an OK typing as it has 7 resistances but it has 5 weaknesses, 1 of which is a 4x weakness (Fairy).
But until images are revealed, we'll have to take this with a grain of salt.
Also, because of numerous preview events in London and San Francisco, there are a couple new images that are interesting. The Pokemon Center is interesting because of the Cafe part to it that seems to be related to WiFi features and the Poke Finder image is interesting because it says Version 1. This means you can upgrade it.
Otherwise, nothing else at the moment.
Edit: Also, according to Serebii, one of the previews mentions that Tackle's base power has been reduced from 50 to 40.