I give credit to News.com for incorporating trackbacks almost a year ago into their news articles as a way of extending discussions. There has been ongoing discussion about the etiquette as was as the long term viability of trackbacks.
Personally, I think they are an integral part of user-generated content and in some cases support for them should be extended. The arena of product reviews is the first that comes to mind:
Why don’t amazon.com and cnet.com support trackbacks in their product review sections? There are a lot of bloggers who meticulously assemble their personal experiences with products and this information would be great for consumers during the shopping process. The blogger gets easy syndication, credit, and a link back. The big company’s get more info and a page rank boost, seems like a no brainer. Heck, amazon could even offer a custom trackback and tie the post to your amazon account for you!