I don't think it's a greatest hits album either. Mike has insisted that MTM, ATS and LT (?) should be listened to in order and in entirety (I didn't follow the HT and Meteora cycles, so I don't know if he said anything similar about those albums). Then why would the band make a greatest hits album?
So I think this is lost in translation, as LPxDC said.
This would be cool.