'Even more exciting is the fact that all attempts to formalize the intuitive idea of “algorithm” or “process” have been proven to be at most equally as powerful as Turing machines. If a system has this property, it is called Turing complete.'

This implies Turing completeness means being "at most equally as powerful as Turing machines", but since Turing completeness means being able to simulate a Turing Machine, I think it actually means being "at least equally as powerful as Turing machines."