The exam (A00-234) will have both performance-based questions and multiple choice, just fewer of each than the full exam (A00-232). The main difference is that you will need to complete the performance-based projects, which were not part of the old A00-212 exam. Yes, there are some content differences. The SQL and Macro content is very consistent with prior content. The Advanced Techniques section has seen more changes, with the loss of Indexes and the addition of some advanced functions such as regular expression matching.
For experienced programmers, I would suggest using the Exam Content Guide to review the topics and then use documentation and experimentation in SAS to learn topics that you are not familiar with or haven't used in a while. Alternatively, there is training, a prep guide, a full length practice exam, all listed on the credential's web page.