I came across this article on 15 year mortgages today. I am a fan of 15 year mortgages as they can save you A LOT of money over a regular 30 year mortgage. We had a 15 year mortgage on the first house we bought and, like clockwork, we owned our house free and clear after 15 years. We then used that house as a rental for a few years until we sold it so nearly all money from our renters was pure profit.
For our most recent home purchase we went with a 30 year mortgage for many of the reasons listed in the article. First, we didn't really know what our income would be and didn't want to lock ourselves into the higher payments required by a 15 year mortgage. We also didn't know how the market would go (it was near the bottom of the housing market when we bought here in Vegas) and also didn't know how long we would be living here.
On the one hand, having a 15 year mortgage forces you to pay off your mortgage twice as fast as with a 30 year mortgage which is a good thing, You build equity much fast, save on interest, and can cancel PMI insurance quicker. On the other hand, if something happens with your income making higher than usual mortgage payments can be a scary situation to be in.
In the case of a 30 year mortgage, if you don't have a pre-payment penalty, you can easily make extra payments on the principal and still pay off your mortgage faster than usual (this take a bit of discipline though).
So it is a personal decision whether to get a 15 or 30 year mortgage, based on your own circumstances, but a 15 year mortgage is definitely something to look into!