From what I've been told, only plan on creating an LLC if you:

1. Want to be able to write a bunch of stuff off as company expense.

2. Don't mind the paperwork.

For liability you need insurance, not protection from an LLC or C-Corp, neither of which will necessarily protect your assets if you are working on your own.

The advantage of a C-Corp primarily is to get business from companies interested in corp-to-corp. If you look on Dice, etc. there are a number of jobs listed as corp-to-corp only. I read that this partially stems from a court decision where contractor employees were able to sue for benefits that weren't even W2, but that if you are under a C-Corp they wouldn't have to worry about that.