The 20th Birthday Celebration. Cartoon Network devoting the entire month of October 2012 to celebrate their heritage past and present. All the fans on forums like Toonzone and 4chan admit that while the network has made some mistakes (the live-action shows, someanimatedduds, all of which have been canceled and barred from rerunning, and never mentioned in the celebration), they praise the network and thank it for 20 wonderful years of memories.
Not to mention, they were able to bring Christine Cavanaugh out of retirement to voice Dexter one last time before her death two years later.
After the death of Chuck Jones in 2002, what did the network do? They aired four straight hours of Jones-directed shorts (including the banned "Frigid Hare"note a Bugs Bunny cartoon that had Bugs doing battle with an Eskimo. It was banned from the June Bugs special that was supposed to have 12 Bugs Bunny cartoons that had racially offensive caricatures as villains) the following weekend on The Looney Tunes Show (not the sitcom, the installment show featuring nothing but Looney Tunes and Merrie Melodies cartoon shorts).
The In Memoriam segment from the Fancy Anvil Awards show, which presented tributes to William Hanna, Chuck Jones and Maurice Noble.
Their tribute to Joe Barbera when he passed away in 2006.
Say what you will about the CN Sayin promotion, but if you ask me, I think it's kinda sweet to see so many kids saying how much they love the network and its shows.
The fact that Samurai Jack, a show that is often considered to be Cartoon Network's best yet, is being brought back with new episodes is not only awesome, but also heartwarming when you consider this: one aspect of the channel's Network Decay was the seeming hatred and dismissal of straight-up action shows such as Sym-Bionic Titan and Beware the Batman. Despite this (and the show being planned for airing on [adult swim]), the new episodes are still being produced by Cartoon Network Studios. While too early to tell, it could easily be a sign that Cartoon Network is once again beginning to see the merit in action shows.
This is obviously Boomerang's answer to [adult swim] and TeenNick's throwbackblocks. The channel is airing classic shows at the same time as those blocks to target older viewers. Back when Boomerang relaunched, they only did this after dark and the only classic Cartoon Network show they aired was Foster's. The fact they're actually building on this is something to appreciate.