When it comes down to choosing between bullet security cameras vs dome security cameras it all comes down to what you want to accomplish. You see there are two schools of thought. Some believe that criminals are deterred by the sight of security cameras and will choose another target. Others believe that the presence of security cameras actually encourages the thief showing you have stuff worth guarding.
Although both thought processes have some merit, times have changed things rendering one invalid in today's world. The invalid thought is that it encourages theft. I say this because these days security cameras are so prevalent that even poorer low income families can afford to buy and use them for safety.
With all being said it really just comes down to functionality, costs and installation location. As far as functionality goes, both types have infrared capabilities which allows you to see in the dark so be sure whichever model you choose has this capability. The reason being that you don't want to be “camera blind” when the sun goes down.
As far as costs go, both types are affordably priced and vary depending on which features you choose as well as how high of a quality picture you want. I suggest the go for the highest resolution you can afford since it would be a shame and a waste to capture the faces of criminals yet not be able to make them out enough to be useful to law enforcement.
So far as you can see you can still go either way right now with a domed security camera or a bullet security camera. Where the true choice difference comes in is the installation.
Dome cameras are great for doorways and overhead installations although they can also be installed on the side of buildings or poles. It just isn't their strong point which is the overhead installation options. Most dome cameras look down and to one side unless you get one with pan/tilt and zoom (PTZ) capabilites so you have to take this into consideration for proper installation.
The bullet camera because of the shape (see picture to right for example), is better suited for the sides of walls and up in corners as their view is generally wider but the fall short when trying for overhead views.
Another benefit of the dome camera is that many come armored. This means that it is much harder to disable the armored models since they are designed to withstand quite a bit of impact damage without failing.
Instead of deciding between the two types of cameras I personally recommend a combination of the two. Use the dome cameras over doorways to catch anyone coming in or out of the doors and then use bullet cameras up high on the home or a pole getting a wide view of the area you are attemoting to secure.
The dome cameras are harder to notice since they lay flat (not including the large PTZ dome cameras) so they don't have the same amount of deterrent effect as the bullet cameras do as they come in sizes from small (like the one shown above) to rather large and easy to see.
Think carefully about your desired installation locations and see what looks like the best fit for you and your individual needs. Remember you can always use dummy cameras to help bolster your security setup without adding a ton of cost to it.