Official story and features:
"Sega's legendary mascot Sonic The Hedgehog makes his historic multi-platform debut and embarks on his biggest adventure ever, with his trademark blazing speed and a new gameplay twist in "Sonic Heroes." Sonic and his friends have evolved, adopting a configuration feature that lets gamers control three playable characters simultaneously, using Sonic's speed, Knuckles' power, and Tails' ability to fly, to conquer massive worlds. This team-based gameplay marks the next evolution in Sonic's gaming career, taking platform gaming to a completely new level. Using the three formations and the powerful moves that each team member has, Sonic and his friends combine forces to battle the ultimate evil."
Story from Sega press release
"- Play as one of four teams for a total of 12 playable characters - Team Sonic, Team Dark, Team Rose, or Team Chaotix - each with their own unique signature moves and story line
- Each team boasts multiple specialized stages with unique missions and CG movies driving each "team" story forward
- Experiment with team formations to learn the best way to defeat enemies, solve puzzles, and navigate massive environments
- Each stage contains multiple paths and missions for maximum replayability"
Features from Sega press release
Sonic Heroes is really fun but after a while it gets pretty annoying. Whenever Sonic runs too fast for Tails and Knux, and they take a wrong curve into the ocean, they jump right out. In the Sonic games I play, I want to play as Sonic and any of his other friends SOLO.
-- From Christian
I think this game is good, but there is quite a bad replay value. Except that, very good indeed.
-- From y
I love this game!! It rocks my socks!! Knux is the best :D along with Espio and Charmy, of course!! lol Overall, this game kicks butt!
-- From Katie
Sonic Heroes comes out in January supposedly, but it's looking to be the best 3D Sonic game yet, so look out for that.
-- From RayCRP