I liked it. I like Don Hertz's style, but maybe the hype ruined it for me. To be honest, this is more like a good Newgrounds flash animation than anything else. Interesting, but it didn't change the way I see the world. I thought the short was going to be some mind-blowing, paradigm shifting 17 minutes, but it was just some neat little animation (the animation itself wasn't anything to write home about).
(I wrote the above on a Don Hertzfeldt subreddit, the rest is for your eyes only

Ok, now I'm sad. One person does funny-enough crude animations and is considered a genius and wins prizes left and right. That would be ok. I liked both "The World of Tomorrow" and "Rejected" but there are a lot of animators, artists and filmmakers doing the exact same thing (sometimes with even less crude animation) and will never get the recognition he gets. This brings me more existential anguish that "The World of Tomorrow" could ever give me.
Neat short 7/10