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Here are two interesting articles on this matter. The first is from National Geographic. Here are a couple of quotes:

The finding has excited the scientific community especially because it opens a window onto a period near the time when humans and apes diverged from a common ancestor. Virtually nothing about that period is known, as most human fossils are considerably younger.
Various aspects of the new fossils could force scientists to rethink some basic theories about human origins, according to several scientists who were not part of the research team.

Then later,

Lieberman saw the skull and, like some other observers, said he was particularly intrigued by the creature's unusual mix of both primitive and advanced traits. The braincase is chimp-like, for example, but the face, teeth, and somewhat flattened head resemble those of humans.
"What's most astonishing is that the facial features are like those that we don't see until 1.8 million years ago in the genus Homo. It is more Homo than australopithecine," he said, referring to the best-known group of hominids, which appeared in East Africa three to four million years ago and whose fossils have provided most of what we know about the earliest human ancestors."

Then, Lieberman again, in answer to a question:

So, is the new skull fossil a hominid—perhaps our earliest known ancestor?
"It's very hard to be sure, but I think it's a hominid," said Lieberman. "But whether it was the earliest hominid or the earliest ancestor of anyone living today, we can't tell."

The National Geographic article also quotes experts disputing Lieberman.

The next source is Nature Magazine. A quick quote from this article states that scientists have indeed noticed that the muscles attached to the back of the scull:

"When I first saw the skull I thought: 'Gee, it's a chimp'," says anthropologist Daniel Lieberman of Harvard University. Toumaï's brain, for example, was roughly chimp-sized. A closer look "blew my socks off", he recalls.
Sahelanthropus has many traits that shout 'hominid'. These include smaller canines, and thicker tooth enamel than apes. And the point at the back of skull where neck muscles attach suggests that Toumaï walked upright.
Many of Toumaï's advanced features are missing from later fossils such as Australopithecus, but reappear in still later species that are classified as Homo.

And to satisfy those who will note that this will force changes in the "ladder of evolution," the article states that this will force changes in the "ladder of evolution."

Toumaï is the tip of that iceberg - one that could sink our current ideas about human evolution. "Anybody who thinks this isn't going to get more complex isn't learning from history," says Wood.
"When I went to medical school in 1963, human evolution looked like a ladder," he says. The ladder stepped from monkey to man through a progression of intermediates, each slightly less ape-like than the last.
Now human evolution looks like a bush. We have a menagerie of fossil hominids - the group containing everything thought more closely related to humans than chimps. How they are related to each other and which, if any of them, are human forebears is still debated.

Read both articles. There is a lot more information -- and controversy -- than Jeff Farmer prints.