I agree with Ceilick that this is a little underwhelming, being that this is a glorified update to Keen 4, and
based on what Tom Hall talked about, the final game would've been something closer to Mario 64.
But then as K1n9_Duk3 mentioned, there was that Zoo level that Tom Hall was intending to make, and looking at this quote by Tom:
"My last idea for Keen 7-9 was a game world [that] was 3D, and at certain places the camera rotated with you for different games. " gives me an idea...
Maybe the zoo would've been a fully fledged, 3D hub world and lets say you go to the "Gnosticus IV wing" of the zoo, you'd be transported to the world of Keen 4, which would play as a sidescroller, like what we're seeing in this demo.
Sonic Jam did the same thing on the Sega Saturn-- you run around in a 3D hub world, which gave you access to the previous 2D games.
At least, that's how I can mentally combine both ideas of different camera angles and also yet something similar to Mario 64.
And oh yeah, I updated the
Keen wiki page for TUIT-- I noticed it was missing Joe Siegler's quote, which mentions Tom Hall's zoo idea and I added a link to this video.