The term 'Vibe Scepter' was a rather poor choice by the developers. While 'Vibe' can mean one's emotional state, it also can mean 'vibration' which when combined with scepter can lead to unfortunate innuendo. One has to wonder why they didn't make the Artifact of Doom the Vibe Crown or the Vibe Star instead?
Alternate Character Interpretation: During the final battle with Bowser, he seems pretty willing to not hold any of his punches against the Princess, and isn't even perturbed when one of his minions called her a "brat". Perhaps in a state of Vibe Scepter-induced Calm, Bowser temporarily realized the futility of constantly pursuing Princess Peach, and that the only way to ever truly take over the kingdom is to stop kidnapping her and to actually defeat her?
Fan Nickname: Most commonly, Peach's Vibe Power is "PMS Power".
Game Breaker: Practically every upgrade is one of these. Each one makes it more and more difficult to die.
Hell Is That Noise: What happens to the music when Peach uses her Anger Vibe Power, as it becomes slowed down, deep, and warped. This is especially true during the hot air balloon segments, which require the player to keep Anger going for an extended period of time.
The fact that Princess Peach's main mechanic is the Vibe Powers, or more simply put, weaponizing radical mood swings. Not that the Vibe Powers were bad, nor was this her only power in this game (she also used Perry the Parasol as her primary weapon), but the fact Peach's first solo game saw her fighting with emotions continues to haunt this game's reputation even to this day.
In addition to that, many people remember this game as one giant dildo joke due to the Accidental Innuendo at the end of the game pertaining to the "Vibe Sceptor".
Scrappy Mechanic: As with many DS games that utilize this, the mic controls during the submarine levels, in which a player has to blow into the mic to get Perry to shoot bubbles at enemies. Not only is it clunky having to tap the A button to keep afloat while trying to do this, but during these levels all the other buttons are unmapped, so it would have been just as easy to have the bubbles be controlled by one of those buttons, or even the shoulder buttons, instead.
So Okay, It's Average: Despite receiving above-average reviews from critics, and actually selling quite well, many fans claim this game is really just decent overall, and while it introduced some new and interesting concepts and mechanics, it was too easy and short to be memorable. Sadly, this has really hurt the franchise overall, since it apparently wasn't good enough to be a hit or a cult classic, but wasn't bad enough to be infamous. It just sort of ... happened, and now is barely talked about anymore. Nintendo on occasion does mention the game, and it has its share of fans, it's just not an all-time classic game.
Stop Helping Me!: Some people dislike Perry simply because he will always tell you exactly what you need to do to solve a puzzle or how to defeat a boss, thus making the game too easy and taking away a lot of the exploration potential. Then again, to even get these hints you have to hit his blocks, so all of his tips are completely skippable.
Take That, Scrappy!: During the introduction cutscene Bowser's general captures Toad (along with Mario and Luigi), referring to him as 'that mushroom-headed loudmouth'.
That One Boss: Bowser. Has hard-to-dodge attacks and it's hard to figure out how to beat him. Luckily, you're healed between his two phases. That being said, all of Bowser's attacks do have a pattern to them as well as a tell, and if things get rough Peach can always camp out in the corner and use her Calm-induced Healing Factor to restore her health. Really, the hardest part of the fight is trying to time the bombs to explode right in the sweet spot of Bowser's giant face while simultaneously dodging his attacks.