I have been waiting for an official certification from Microsoft on Power BI.
And finally I saw the exam opened up. 🙂
Even though it is still marked in Beta but you can go-ahead and schedule if you want.
Or you can start gearing up with necessary technical knowledge to complete the certification.
Please check-out below link which has everything that you need to know and get prepared for it.
Find out more @ https://www.microsoft.com/en-us/learning/exam-70-778.aspx