Newer automotive GPS units can do much more than tell you where to take your next turn.  Some newer units include things like direction to the nearest roadside assisitance, restaurant reviews, speed detection, and more.  A new Navigon unit even shows you a virtual picture of upcoming interstate interchanges, and shows you which lanes are best for you.  Bottom line: features are different on most every GPS, so do some shopping around to find out what's best for you.

Cell phone GPS is also getting packed with useful features.  You can now use your cell phone to find the best gas prices near you, or even look up movie times and information on local events.  Many phones will also do turn-by-turn GPS routing.  However, due to the size and shape of the phones, they can be awkward to use in a car.

Many of the features found in phone GPS might be better suited to automotive GPS- but the problem is that the content for those features is delivered by cell networks.  That means it may be a year or two before hybrid units can do it all.

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