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So, I was on Wikipedia last night and the entry for "Greatest Hits" mentioned that Foxy Brown is not on the "Greatest Hits" version of "Running Your Mouth". After listening to the audio that has been released, that does appear to be the case.

For those that don't know, "Running Your Mouth" (with Foxy Brown) was released on a Target bonus disc when "Duets: The Final Chapter" was released. "Want That Old Thing Back" was also on that bonus disc.

The Recording Industry Soundbank mentioned that this was the first single for "Greatest Hits". Although, as of now, it doesn't look like they are going to make a video for the track, as I had suggested.