Today Khronos released the SYCL 1.2 provisional standard, you can read the specification and the press release.   This is a provisional standard, so you can provide feedback about it on the forums.

You can also watch my YouTube video that gives a pitch for the standard, and how it fits in with things.  This video is light on code details, because I want you to understand the basic ideas and then go read the specification for yourself.

Note that this video is unofficial and is not endorsed by Khronos or affiliated with it, the views in here are my own, and my slight mistake and audio stumble at the end is entirely my fault.