Which is better Facebook or Twitter? I prefer Facebook over Twitter. That's a better and fairer question to be asked. I use both tools and will continue to do so for the feasible future.
It is not an "either, or" situation. You should continue to use both. And I would further say you should use both. The article below has some good pros and cons of both Twitter and Facebook.
I primarily like Facebook because of its "huge, rapidly growing installed user base". Also, it has a developing "gift giving" module. Probably, my biggest dislike is the "bigness" which requires time to master.
I most like Twitter because of its requires you to be brief to get your initial message out. You have to get people insterested in 140 characters. It is a microblogging application. My biggest dislike is the "newness" of the application.
So Which Social Network is the Best?
While zealots will immediately point to either Twitter or Facebook as being superior, the truth is that each has its advantages and disadvantages and will tend to appeal more to different types of people and for different reasons. Each can have great or little value to anyone; it really depends on what you are trying to accomplish in a given situation. Consider some of the pros and cons of each network: