ICANN to Incorporate TLDs Already In-use?

An anonymous reader asks: "I recently found an article at cnn.com about ICANN considering new top level domains. Some of the proposed TLDs have already been introduced by YOUCANN such as .xxx and have been available to the public at select registrars such as new.net for quite some time. If ICANN incorporates already existing TLDs how will this impact those who have already registered for domain on these TLDs? What implications does this have and how will the ramifications impact how businesses view and utilize the web?"