"The original operational date was set at Nov 1st 2006. Programming and development began in 2003 but actual processing on the system was delayed until 2005. The system initially processed only 1040EZ tax returns, the simplest type of electronic tax returns. In 2006 the capacity was increased for the system to begin processing a limited number of more complex 1040 forms and other support forms. In 2007 the system began to process Schedule C forms and other more complex tax forms.
"Because the system is still unable to handle the full load of IRS tax returns, a hybrid approach is used by the IRS with the overwhelming majority of tax returns still being processed with the old system. Current processing loads and returns done by CADE are used for testing purposes to determine the systems functionality.
"The system, although beset by regular set backs due to funding, is expected to be fully operational by 2012" (Wikipedia article on Customer Account Data Engine, accessed 12-27-2008).