The rumored PS4 Slim appears to be real, as confirmed by Eurogamer, that visited Twitter user shortman82, who reportedly purchased the console from the online auction on Gumtree.

They were able to take a video of the console booting up, and you can check it out below.

This appears to confirm the legitimacy of the hardware, unless someone has really great engineering skills right there, but that's unlikely.

Update: the video has been taken down by Eurogamer "upon taking legal advice." No further details were provided.