Adored by the Network: Cartoon Network gave this a huge buildup: a "sneak peek" six days before the premiere (which also aired on Boomerang and streamed on the website), a countdown bug on-screen the day of the premiere, and at least one rerun a day for the entire week afterward.
The Latin American version of Cartoon Network brings this trope Up to Eleven. They went to such extent to dedicate a whole day to the show. They also use them to announce the new stuff of the month and air reruns three times a day, everyday, and they often air clips of this show during the commercial breaks for no reason at all.
Dawson Casting: Aside from the Watterson children, kids in the show are played by adults.
Gumball was voiced by Nicky Jones (aka Chowder) in the pilot.
In the first season Mr. Small, Tobias, Banana Joe, and Alan were all played by Rupert Degas and Ms. Simian was Sandra Searles Dickinson, while in the second season these roles were all taken over by Hugo Harold-Harrison.
Both Gumball and Darwin have been re-cast for Season 3 due to their voice actors hitting puberty.
Short Run In Peru: Several episodes have aired first in Brazil (Portuguese dub), France, Spain, Central and South America (still in English), and Australia.
Talking to Himself: Most of the dozen plus named students in Elmore Junior High are voiced by a few people, so this happens a lot. In particular, every non-adult female but Anais, Tina, and Sussie is voiced by Jessica McDonald.
What Could Have Been: The original pitch for the show was in an "Early Reel". The most noticeable differences are the fact Darwin was animated in CGI and Gumball had a square head, though other characters looked different too. Teri was also a boy originally.