A boxart for the X-box 360 version of Sonic & SEGA All-stars Racing popped up on Chris Lewis’ (Sega of Europe’s Box art designer) personal website. On the back of the package it clearly depicts Meryl’s Codec number a picture of Banjo and Kazooie who would most likely race in the same kart.
Since then the box art has been pulled, so I would say that is a pretty good sign that the duo may appear in the title.
This raises the question if the other versions of Sonic & SEGA All-stars Racing will feature console specific characters as well. Maybe we will see popular characters such as Raymond Bryce from Disaster Day of Crisis for the Wii version or the main character from Mole Mania for the Nintendo DS version.
You can check out the box art after the jump
(Source: Sonic Stadium)