- Broken Base: The series as a whole. Is it too similar to the original? Fans of the late 90s, early 2000s direct-to-video films such as Zombie Island and Cyber Chase often complain the reboot is too strict to formula and generally not as fun (or well animated). Fans of the original pre-Scrappy cartoons may complain that it's too "modern" and "realistic" compared to the older shows, along with over-lampshading the old formula and not being as scary.
- Ear Worm:
- The theme song by Simple Plan.
- As is the norm, all of the Hex Girls songs.
- Fandom Rivalry: With Scooby-Doo! Mystery Incorporated. They're two popular, new-millenium modernizations of the series on two polar opposite sides: What's New? keeps things mostly traditional and more true to real life, while Mystery Incorporated vastly reworks the personalities, designs, and general series. Both series clearly knew what they attempted to do but clearly rubbed certain sides of the pre-existing fanbase the wrong way. It will be rarer to find someone who liked both equally rather one that will claim one was more enjoyable to the other. As time moved on the Scooby fandom would have further ruffles about what occurred since and whether they improved on WNSD and SDMI.
- Friendly Fandoms:
- Hilarious in Hindsight: In the teaser of "Toy Scary Boo", the "living" Spaceman Swinton dolls build a long ladder out of building bricks resembling LEGO, which now have Scooby-Doo sets.
- It's the Same, Now It Sucks!: To some, the return to the previous formula was fine, but it's the fact that the only thing that was different was the overt lampshade hanging and certain mannerisms of the gang. It was regarded nice returning to the formula, but doing little variation with it was something of a major problem for some.
- They Changed It, Now It Sucks!: While some people praise the show and hail it as a return to "the good old days," this show has received criticism, mostly from those who preferred the older 1970s series, due to changing the character designs and animation, music and sound effects, trying to make it more "hip" and "current," among a few other things.
- Ugly Cute: The bat that Shaggy and Scooby thought was Fred in "The Vampire Strikes Back".
- We're Still Relevant, Dammit!: In particular, one episode featured a guest appearance from obscure pop singer Lindsay Pagano, who at the time was an up-and-coming singer associated with Warner Bros.note but quickly fell into obscurity outside of reappearing on The Voice.
YMMV / What's New, Scooby-Doo?