360's Backwards Compatibility Weak?

GamesIndustry.biz is reporting that the backwards compatibility that Microsoft offered up at the Monday press conference may not be anything approaching what we're used to. Due to the massive design changes in the shift from the Xbox to the 360, Xbox titles may have to be recompiled in order to work on the next-gen console. From the article: "The news has raised more questions than it answers, however, as it suggests that gamers may need to purchase titles they already own in order to play them on an Xbox 360 - and almost certainly means that only a sub-set of Xbox games will ever be playable on the new console." Update: 05/20 15:08 GMT by Z : The article has been updated with a quote from MS specifically saying that gamers will *not* need to repurchase Xbox titles to play them on the 360.