This is more a mixed review than a negative one.
The gameplay is basically Snake, but in Pac-Man-styled levels. Navigate mazes filled with corridors, collect all the pellets, and reach the exit, all without running into your own body, which elongates as you eat pellets. Familiar with Rattlesnake from Windows Entertainment Pack, which I recall had easier levels, I wanted to see how this compared.
It was fun for me in the beginning, but this was because the levels started out small enough that you could see the entire playing field on screen at once. By the time you access world 2 of 3, they become so big that even the zoom button won't show you the whole thing. This is important, because as you progress the levels become trickier, with more bottlenecks that you have to identify and clear early before emptying the rest of the stage. So, there's an increasingly heavy trial-and-error aspect that I don't really like. In addition, Millie's body becomes so long in these larger levels that, in order to eat those last few pellets you're missing, you have to take the long way around the whole area multiple times, just to avoid running into yourself. I've gone from taking 1 or 2 minutes to clear a stage, to taking multiple 5-minute attempts to clear just one, and I'm not even halfway done with the game as of this writing.
The zoom button pauses gameplay, and because the default camera is often zoomed in too close to anticipate bottlenecks and such, you'll have to zoom out constantly to make sure you aren't going down the wrong path. Not only does this make the pacing tedious, it suggests the developers wanted to enforce a memory aspect, which again is something I don't really like.
There are powerups, like hammers that break cracked walls and sirens that let you go both ways on one-way streets. I was hoping these would add variety to the levels, since there are nearly 100 of them, but they never seemed to make enough of a difference in the gameplay. They activate instantly upon pickup and last less than 30 seconds, so you have to know where to use them first, but again, since the levels become so large, you often have to make a preliminary attempt just to discover all the noteworthy areas. I feel the levels become challenging less by creative use of different mechanics, and more by increasing level size and number of bottleneck areas.
If the premise interests you, and the above points don't bother you, go ahead and give it a try. Otherwise, be warned that it becomes much more difficult than the mood of its trailer suggests.