Any tax-related questions are best addressed to a tax professional or to the IRS. You can find information about reporting and filing requirements for independent contractors at http://www.irs.gov. Our answers can't be considered authoritative, but here is a summary of the situation as we know it.
Being an IC Pro has no effect on your tax obligations or reporting status. JobSlinger does not report on your earnings -- we have no information on what your earnings are. When you register as an IC Pro, that doesn't mean that we gather together all your earnings and report them to the IRS as if you were working for a single company, which you aren't. Each employer (meaning each mystery shopping company you work for, not JobSlinger) is legally required to report your earnings to the IRS IF AND ONLY IF your earnings FOR THAT COMPANY exceed $600 for that tax year. Whether you are IC Pro or not, a JobSlinger member or not, that will not change.
JobSlinger doesn't employ shoppers and isn't involved in whether or not companies send you a 1099. If you want to know if you will be receiving a 1099 form, contact the companies you work for to see what forms you can expect to receive, if any.ceive, if any.