BBCnews is carrying this article summarizing a recent archeological discovery that could crank the date for the invention of writing back to about 8,600 years ago, fully 2000 years before the mesopotamians came up with it. As the article notes though, it's still too early to tell if this is writing or "just" decoration. Human languages, even literate ones, can change dramatically in just a century or two (anyone who's tried to read Shakespear without footnotes can attest to this), let alone 5 millenia.