Unfortunately, many people were turned off by this movie; first problem being that it was not so much a movie as it was a long cartoon. Never the less, there was enough content to fill the time.
I don't quite understand what beef people have with the story line, it wasn't much more of a deviation from something you would encounter in one of the games. The only difference this time was that it was the first introduction of Sonic into a "real" world (disregarding the US cartoons, because this movie passed under the inspection of Sonic Team, making it essentially legit). I thought it proposed a decent solid story line, it introduced the characters, the problem, etc etc...
The movie was the best animated representation OF the whole Sonic/Robotnik rivalry, while still keeping the same "friendship"/interaction with all the characters that people have grown to know; Sonic and Knuckles giving each other a hard time, Tails following Sonic around like a puppy, Sonic and Robotnik fighting while Sonic always remains light hearted about it all in the end.. Although they introduced alternate, "non-Sonic" characters, this is also actually the best animated representation of a world that Sonic exists in. The president reigns over "South Island", which is a place the Japanese manual for Sonic 1 references when talking about the Chaos Emeralds. Sonic and Tails' trek to the center of Robotropolis brings them through scenery and obstacles that are immediately reminiscent of the early Genesis games (I loved the scenes with the Caterkiller and the Buzz Bombers).
The inclusion of Metal Sonic was the pinnacle of the movie, though... Metal Sonic has developed a HUGE fan-base in the Sonic community, and it was only proper he finally be given a real character background and personality. There are multiple versions of him throughout the Sonic games, he had a different design for every one of these games: Sonic 2 (Genesis/MegaDrive), Sonic 2 (GameGear/Master System), Sonic CD, Sonic & Knuckles, Knuckles' Chaotix (final boss), Sonic Heroes (final boss). But the design that caught on the most was from Sonic CD, Chaotix (first encounter w/ him), and Heroes (after his new form was defeated, he reverted back). While alternate universes exist within many other long running series (be they TV, Movie, or games), no real beginning of Metal Sonic was ever explained or described, other than the game manuals saying Robotnik designed a copy of Sonic. The movie gave life to this character.
The English voices weren't the greatest, but they at least fit the characters very well... Sort of like how the American music for Sonic CD is more appropriate for the level designs than the original music is, despite the original music being more popular. They should have used some of the voice actors from the animated cartoons here in the US, rather than getting new people; but the voices were still better than the English voice actors Sonic Team used in the most recent Sonic games.
The animation was excellent, cleanly drawn, very expressive character movements. The animators captured the way Sonic moved and attacked perfectly, about as "realistic" as you can get with animation.
Take reviews with a grain of salt... don't believe just one person's opinion. I say it's good, other people may say it's bad. See it for yourself, just don't approach it expecting a miracle. It's a fun getaway, retreat from the norm...and savior from Sonic X.
