
I am a geologist not a physicist, so don't expect a mathematical explanation to this, however I'll give you the basic idea.
In basic terms, yes the magnet will fall faster. However the difference in speed will be incredibly small that I doubt you would ever be able to measure a difference in speed.
The attractive force due to magnetism, much like the attractive force due to gravity or a difference in polarity in electrical charge, decreases exponentially away from the surface of the body in question. The key for a magnet falling to earth, is that the area of high concentration of metals, is in the earth's core, which is a huge distance from the surface of the earth. Therefore the attractive force between a magnet and the metal in the earth's core will be so small it could probably never be measured.
Therefore the magnet will fall faster, as it has the force of gravity plus the force of the magnetic attraction pulling it towards the earth. However in practise, this extra force is so small that if you dropped both from several miles in the air, they would still hit the earth at the same time, or such a small time apart that it would look like they hit at the same time!
To add to that, the problem is a bit more difficult (I reckon, not that I actually tried any of this out). A magnet has two poles, and if two opposite poles face one another, they will attract. If an object falls though, it will usually spin quite a bit, meaning that the magnetic force will be pushing and pulling in such a way that the net influence will be zero.
On top of that, the magnetic field will have to be perpendicular to the Earth's face in order to add to the gravitational force. The only areas where the field is more of less perpendicular are the North and South pole, so please go there and try to drop a magnet in such a way that one pole faces down and the other down, and find a minute difference? Best of luck!
If an object falls within the atmosphere from the height of the ozon layar for example, it won't matter. Because the maximum drop velocity depends on the counter force provided by it's air resistance. Basically the faster you fall, the more air resistance. It can't really fall faster than the equilibrium where the drop velocity equals the drag. A magnet won't add speed to this any more.
Outside the atmosphere it might accelerate the fall towards gravities center, but on entering the atmosphere the same equilibrium rule will apply making the influence of the magnet probably negligible.