Dre spoke to power 100, They played number one then dre phone'd in. They asked about eminem and the album, dre had no comment, but said the song number is actually not titled number 1 someone made that up, and it was suppose to be a detox track that eminem worked on, and dre was not sure how em wanted the flow, so em rapped dre's verses and sent it to dre via email. Dre said seems like someone got onto his email and started sending this song out. Dre said within Interscope is his guess, and he is not gona use this song now becuz of its early release and that its not completed.
source: power 100, LA radio Station.