There are definitely a lot of pros and a lot of cons. You can save a lot of money, or at least I did. You can also get pretty good financial aid. They gave me the first year free since I lived in the city and graduated from a city high school. You can get a lot of general classes out of the way. The cons? You have to worry about transferring. Then there are many students who end up dropping out instead of transferring.
I agree with Macon. However, in today's economy I would lean heavily toward the 1st two years at the community college just because of the cost. Credits transfer. Just find out which ones you need and what transfers.
I actually considered doing this, but in the end just decided to go to a 4 year college. By going to a community college for the first 2 years, you can get rid of some of your Gen Ed classes, and save quite a lot of money. My biggest fear in doing this, would be joining a brand new school 2 years later than most people. Would I make new friends? Would I have a good experience? would I Feel at home?
The biggest advantage would be saving money. A disadvantage for some might be that there is less of a "college experience" although that might actually be an advantage for others. If you want to save money and focus on your studies, attending a community college sounds like a good plan.