While I totally understand why you're angry, I'm almost certain Apple's app review team does NOT have access to pre-release versions of iOS, so this probably didn't happen because Apple was working on similar functionality.
Now, Alaric's app is probably very interesting, but why block it when others existed (and did the animation more poorly)?
Whomever that person is now (Jony Ive?) probably got ahold of this app and did the same thing.
Very easy to hide all of this under the veil of 'we were already working on something like that'. The author even acknowledges as much. So blatant theft is basically impossible to prove. But it's pretty naive to think that does not go on.
Example: an internal 'is this one of the coolest apps you have ever seen?' option given to all app reviewers. One guy whose job it is to review all apps where that box was checked. If he agrees, he sends them on to somebody on Jony Ives team. If they agree, they send it on to Jony.
At the end of the day, that is just a weather app with cool graphic and the guy reviewing apps probably sees a shit ton of those per week. It would take something significant or sufficiently unconventional for him to start a buzz inside Apple.
(BTW: not criticising the guy, he is a dedicated developer and Apple let him down. But let's keep stuff in perspective)