Pretty sure they said 23 characters, and 23 have been revealed http://www.tssznews.com/2012/10/23/several-previews-reveal-more-info-on-sonic-all-stars-racing-transformed/
Either way, I'm just glad they have Vyse, NiGHTS/Reala (even though they messed these two up), pissed that they added Gillius over Tyrus, ticked that there's still no Toejam and Earl, despite all the effort Sumo, and the TJ&E creators put into trying to get them into the first game, no Phantasy Star characters, and no Streets of Rage characters. Hell, there are tons of characters getting left out. Bayonetta, Resonance of Fate, Valkyrie Chronicles, Sakura Wars, Shining Force, Panzer...okay why is Sega a dying franchise with all of these under their belts? Seriously, Sega Smash Bros time... But anyway, primary, I'm happy that they have Vyse.
What? That can't be. They said there were 29 characters across all 3 platforms.
Even if that were true, why would they stop at 29? Seems like a weird number to stop at. They might as well go the extra number to make it an even 30. Or take out Ralph, and make it 28, which would be preferable anyway.