The big changes coming in SQL Server 2017 are the Linux version and the addition of Python as a language used to analyze data. In SQL Server 2016, we had the R language added, and quite a few people have been on crash courses learning R, or worrying about the fact they don't understand how to write an R script. Now many of these same DBAs and data professionals worry that they also need to find time to pick up some Python and Linux.
I really like Python. I spent some time with the language and still dabble here and there. It's a clean, easy to write and read language. My son took an intro CS course this spring in college and we shared some programming thoughts and ideas in Python. If you're interested, I'd recommend the Dive Into Python book, as well as the meeting series from SDTIG. If you want to learn R, I've been dabbling at TryR from CodeSchool. There are also resources from Grant Fritchey and Buck Woody. For Linux, there are tons of resources out on the Internet. I don't have a recommendation, but feel free to leave one in the discussion.
If you are a data professional that works with data scientists or others that might want to incorporate some machine learning or complex analysis inside SQL Server, do you need to learn R and Python? Is that the feeling that you have? Are these languages require to ensure that you can perform your job?
I'd argue that for many of us, we don't need to understand the language or be able to write R or Python scripts that are being run in SQL Server, or even in a tool like Power BI, to support our users. We should understand how to execute these scripts, and maybe how to correct simple typos. A working knowledge of HTML has come in handy many times for me when helping users display their data and a quick change was needed. However, I wasn't the person you'd call to design a complex CSS and interactive HTML pages. I can just fix a few simple mistakes.
You might feel differently, but I don't think most SQL Server professionals, developer or DBA, really need to learn R or Python. Feel free to do so if you like, and I'd put in a recommendation for Python, which I really like, but I don't expect that either one will be a significant part of your job in the future. Learn Linux if you want to experiment with another OS, but for the most part, SQL Server on Linux is just SQL Server. Learn some rudimentary Linux skills, but spend most of your time making sure you understand the SQL platform and you'll be fine.