That my friends is a personal question that we all must decide for ourselves.
If you feel strongly that China's human rights record stinks or their annexation of Tibet is unjust or you don't want to support a country who is Sudan's largest trading partner or you simply don't want to support a hard fisted communist regime AND that boycotting a huge sporting event held there will send the proper message to change their policies, by all means, do so!
If on the other hand you feel that by boycotting the Olympics in China, you will be destroying an amazing non-political, world sporting event and thereby punishing many athletes from all over the world who have dedicated their lives to this once in a lifetime event, by all means, do not!
I think the problem is with the current process. We have a corrupt Olympic system in place run by a bunch of either totally naive buffoons or on the take committee members who decide which country is going to 'get' the Olympics. I can just imagine the bribery and wining and dining that goes on.
Do you remember when Adolph Hitler's Germany was awarded the Olympics? The premise then was that the Olympics are non-political so it shouldn't matter what the politics are of the host country. Right? Wrong! By giving Germany the Olympics back then, we gave a face and voice to the Nazi's. We instantly legitimized Adolph and his followers.
I think I have the solution.
We need to create a new Olympics for democracies only!
That way we will eliminate a lot of the embarrassing, political goings on every time the Olympics are held. Let China, Russia and the rest of the strong arm countries have their own.
At this point we are all part of a faulty process. We must change the process in order to correct the problem. Boycotting the Olympics will definitely punish innocent athletes from all over the world.
The good news is that it will probably cost China billions of dollars to host the Olympics and they ain't gonna get all of that money back!
Between the recent Tibet fiasco, the cost of jet fuel - the price of air fare, the poor world economy especially in the states and the distance of China from the West and Europe (from where most tourists come from when they go to the event), I really think that the visitor tally will be extremely low.
That said, we still need to ask ourselves:
When are going to stop awarding bad behaviour?!