Details are slim -- in fact, we just told you all of them right now -- but we can assume that Alice 2 will have American McGee's name on the cover, and will probably be another third-person action game that takes elements from the Alice in Wonderland story and makes them all edgy and gothy. We will pass along actual (i.e. non-conjectured) information as soon as it is available.
Update: While we've never known Keighley to not be a man of his word, official evidence is always welcome. EA adds that the Alice sequel is in development for PC, PS3 and Xbox 360 by American McGee's Spicy Horse studio. Says EA Partners GM David DeMartini: "EA Partners is ready to help [American McGee] bring his innovative vision for the franchise to even darker, more exciting places."