In an article in Infoworld, Martin Lattig reports that e-commerce companies are not being well served by XML standards.
The problem isn't as much the XML core standards, but the e-business standards being proposed on top of it. The article cites the confusion caused by multiple initiatives, as well as the danger of XML being "appropriated" by single vendors such as Microsoft/BizTalk.
Simon Phipps of IBM is quoted in the article: "The strategy to embrace, extend, and extinguish has not necessarily gone away". Phipps claims that diversity in XML representations is not to be feared -- that it is transformation which will be the key to XML e-business success.