Unfortunately, though, chimps are not bipedal, and they are actually worse at it than we are.
i had heard they expend less energy walking fully erect than we do, not having to swing wide hips back and forth. maybe i've got that backwards, though. the point about the toe does make sense, too.
There is a slew of other characteristics that make chimpanzees unsuited to habitual bipedalism, from skull structure to pelvic shape; and save for those strange little primates like Oliver, bipedalism's never been the preferred way to go.
as an interesting aside, oliver is no longer bipedal in his old age.