Not all light bulbs are made to work outdoors.  Philips and other manufactures produces light bulbs to fill many if not all of your outdoor or exterior needs.  From bug repelling light bulbs to flood and spot lights to accent lighting, you will find what you need here.  It's important to realize that not all light bulbs that are made for the out of doors are made to be "exposed" to the elements. 

What type of fixture are you installing the light bulb in?

There are three common types of fixtures that are used outside.  

1. Enclosed fixtures that do not let any water in but also do not have a way for the heat that the light produce to escape.  These fixtures will allow almost all standard incandescent and halogen light bulbs to work in them but in warm climates it will shorten the life of a compact fluorescent or LED light bulb.  Even though they are enclosed if they are outside the fixture is still considered in a damp location.  
2. Protected fixtures are ones that have an opening but water would not normally get into it (downward facing flood light, front door fixture with an open bottom, etc).  These also require a damp location light bulb.  
3. Unprotected fixtures can allow moisture to get into the light bulbs area (upward facing flood lights for example).  These require a light bulb that is wet location rated such as a PAR style halogen bulb, compact fluorescent light bulb that is rated for wet locations or a LED light bulb that is also rated to wet locations.

What is your lighting application?

If you are looking for security lighting and want to be able to direct and throw the light where you want it (flood light) or are you wanting general area lighting that provides light for 360 degrees around the fixture (post light)?

Is it about efficiency of light volume?

In most cases you have to have a compromise when it comes to lighting.  You rarely can get a large amount of light and not use a lot of power.  LED technology has helped this equation somewhat but you can still not get the same amount of light out of LED light bulbs as you can out of some of the higher wattage older technologies but as the LED's are improved the gap will continue to shrink.  The other thing that is effecting the higher output lights is some of the restrictions the government is putting on higher wattage incandescent and halogen light bulbs.  You are not able to get sme of the traditional light bulbs that are higher wattage (100 watt A19 light bulb, 120 watt incandescent flood light, etc) If a lot of light is need for an application (parking lot, large open area, etc) you may want to look into High Intensity Discharge (HID) light fixtures that use high pressure sodium or metal halide technology.