As mentioned, if you ever get sued because you hurt someone on the job or lose their wedding photos when your hard drive crashes, they can only take your LLC assets instead of all your personal assets, like your personal bank account, your house, your car, your wife, etc.. They can't bankrupt you personally in a lawsuit, only your llc which won't have many assets.
This is not true. Don't think for a moment that you can surrender a couple of thousand in assets after losing, say, a multi-million dollar lawsuit and the court won't "pierce the veil" and come after your personal assets. It can and does happen. A lot depends on the legal environment in your state--some states are aggressive about liability cases, some are not. You just read "I've seen it happen" right in this thread.
Regardless of the organization of your business, you need plenty, plenty, plenty of liability insurance--that's what's going to keep the court out of your bedroom.
Business organization is much more for taxation protection, than for liability protection. That's why--depending on the size of your business operation--sole proprietorship plus the right insurance may be better than being an LLC.
Talk to you CPA and your lawyer about the best course of action for your business and your state's legal environment, and pay attention to them about what each says in his own specialty. Don't take legal advice from a CPA, don't take financial advice from a lawyer. That's why accountants have lawyers and lawyers have accountants.