The GMAT and GRE are offered by two separate testing companies. Students will want to spend time preparing for the exams and each company suggests allowing up to two weeks for official test scores to be available for university admissions committees to review.
The GMAT exam is changing its test sections beginning in June 2012. You will want to study the most current test format if your planned testing date is after June 1, 2012. A new section on Analytical Reasoning will be added to the test and one of the writing assessment questions will be deleted. The GRE general exam was updated in 2011 and allows for some new test-taking strategies.