I can't wait for new material either.
The long wait somehow forces Bowie to make another
huge musical "statement."
He spoiled us rotten in the 90's with so much eccentric
brilliance followed by three "classic" rock albums.
Since his inspiration is truly with family/home-life I could
envision some sort of updated whimsical domestic-art-rock
a' la' Hunky Dory meets Ram-era McCartney.....
or I'd love to see him abandon "rock" altogether & work with different re-mixers/producers for each individual song and come out with another explosive modern electronic-sax-funk album+