The light gray security / safety clip must be removed first. Use a small flat blade screwdriver to gently lift up (or push down, can't remember which way it goes) the center "leg" of this clip, and pull it out. Then you can separate the male / female MAF connection.
Jim gave me a helpful hint, just stand from the passengers side, insert a flat bladed screw driver under the MAF plug lift up until the catch disengages and you have freed the beast. Worked well for me.