Is making your Facebook profile public help you in getting hired?
It would depend entirely on the contents of your Facebook, and the propensity of your prospective employers to search for, and read your Facebook.
Most folks these days seem to view Facebook more as a personal-social site, while something like LinkedIn is viewed as more professional-social. Employers may well view your Facebook, but it perhaps has less importance professionally.
Assuming everything you have ever posted on Facebook reflects well on you professionally, it probably couldn't hurt. (As @keshlam correctly points out in his comment - that's a rather large assumption).