As of Jan. 9, CompTIA has added "performance-based" questions to the Security+ question pool. None of the objectives for the exam have changed and the test number (SY0-301) remains the same, as well. The only change is that instead of asking a multiple-choice questions requiring the test candidate to guess from among four possibilities, a performance-based question requires using a simulation engine to carry out a particular task. The majority of the questions within the pool remain multiple-choice and the actual number of performance-based questions seeded in is not known.
CompTIA first started using this type of question with the CASP (CompTIA Advanced Security Practitioner) and has added it to the A+ exams and others within the past year. Those already certified need not retest since the version did not change. Those planning on taking CompTIA exams in the future, though, should expect to eventually see some questions utilizing a simulation engine in every exam.
Source: www.certcities.com