Why change them for Taichi and Koushirou?I'm confused as to why you're confused. ^^ Yesterday was August 1, "Odaiba Memorial Day" because that's when Digimon Adventure took place. August 1, 1999 and even in the show (Digimon Adventure 02), they pointed out that every year the group got together to celebrate when they first met their Digimon partners and to give their respects to Wizarmon who died that day.
They had an actual event in Odaiba yesterday to celebrate the series' 15th anniversary and they announced that next spring, they'll do another Adventure anime series with the older kids (Taichi, Sora, Yamato, Jou, Koushirou, Mimi) in high school and I guess the younger ones in junior high school (Takeru, Hikari, Daisuke, Ken, Miyako) and elementary (Iori). So to celebrate Adventure hitting 15 years, they're continuing the Adventure anime.
I can't wait for it! Although, some more information about it would be nice. I'm curious about the seiyuu and if they're going to change them for Taichi and Koushirou....or maybe not. Who knows. Maybe they could keep their seiyuu, only have them sound older. I wonder what the story will be. I wonder if an old enemy will appear. Ooooo, I wonder if we'll finally get a proper story with Demon! I liked Demon so much, I went into fic mode years ago and made up my Digimon Adventure 03. lol
Sorry. Just so happy over this revelation. ^^
Taichi had his old seiyuu in Xros Wars. I think Takeru was the only one who changed voice actors in the Adventure game?