PMI-ACP is an excellent addition or even an alternative to the PMI PMP for IT project managers. I will go even further saying it is more relevant for them. Let me summarize how I see it based on my experience preparing for the certification as of September 2015:
- PMI ACP is excellent for people that would like to understand multiple methodologies rather than focusing on one (like Scrum for example).
- It is convenient for people that completed PMP as the PDUs are being collected together.
- PMI ACP is not as mature as PMP and that is visible from the reference materials: a lot of them are blogs, websites etc. In some cases only blogs are currently available for the new version of the exam (note: I didn't go through the new PMI reference materials). I don't personally mind this, but in some cases there are differences on certain aspects of Agile, the question is really what the exam considers the right answer. With PMP you have the PMBOK - here you don't (exam is based on multiple books from different authors).
- There are plenty of materials, but:
- not many are updated as per the new PMI Examination Outline (as of Sep 2015)
- the test questions are based on the materials that the publisher sells (usually as separate course / product) that may or not be aligned with the exam itself. I tried several different materials and I am confident that if you show me a few mock test questions from the most popular materials I might be able to tell you where you took them from.
- There are materials with questionable quality/relevance.