Traditional Grip Pros:

 - Very common in Marching Percussion 
 - Looks 'cooler' (subjective)
 - Easy to play on a tilted drum, harder to play on a level drum. 

Traditional Grip Cons:

 - Harder to keep both of your Right and Left hand sounding the same.
 - Slightly more difficult to learn properly as it involves less common muscles and the motion is awkward to start out with.
 - Harder to move around and play different drums.

The pros and cons for Matched Grip are basically the opposite of those for traditional.

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I personally am and advocate of learning matched first, then traditional if you need/want to. I play them both and my left hand is equally skilled at them and its not very difficult to keep your hands even if you but in a little effort.

Traditional is most commonly used in marching percussion because it is great for playing on a tilted drum (in fact, that's why it was invented). I know many jazz drummers use traditional, but I've noticed that most of them switch to matched when they actually need to move around the kit as traditional isn't as good for that.

In short, traditional will give you some unique advantages, but it also has some downsides. It ultimately comes down to what works for you. :D