Think about it this way. People don't get vaccinated every year.

More and more studies are coming out showing that vaccines stay in a dogs system much longer than was previously thought.
There are also studies linking over vaccination in pets leading to immunosupression in pets.

Also check with your state laws. Here it is not required by law to get the rabies vaccine. Another interesting thing about the rabies vaccine is that even though there is a 1 year, 2 year, and 3 year vaccine they are all actually the same stuff. The only difference is the number on the label.

I have done a lot of research on this and have made the choice not to have my dogs vaccinated again unless necessary. How will I know if it's necessary? Well every few years I will get a titer test to check the levels of antibodies in their blood. I did this last year for Parvo and Distemper and will do it this year for rabies.
Here's a link to more on the subject.

http://ighawaii.com/naturally/newsle...ccination.html