Matt Casamassina posted some gen-you-wine Halo DS footage from a beta that he somehow got his paws on. So there really was a Halo DS which never made it to release. I have no idea if that was it or not.
Edit: Here's the post from Matt's blog:
http://blogs.ign.com/Matt-IGN/2007/10/02/67886/

"The worst part about these reviews is they are [subjective]--and their scores often depend on how drunk you got the media at a Street Fighter event." — Mona Hamilton, Capcom Senior VP of Marketing
*Image indefinitely borrowed from BrainBoxLtd without his consent.







