Jonathan Street has officially released his version of a Complete API (for Complete.com) to grab traffic information for a particular site.
With the exception of a link from the homepage, which is apparently in the works, Compete has made good on the points I raised so it's time for me to fulfil my part of the deal and release a PHP5 wrapper for the compete API.
The wrapper is simple at this point, only containing only a few methods to make the connection with Complete.com, generate the query and pull out one of three bits of information (including the traffic).