I agree with you that YouTube works wonders for publicity purpose esp in DIY but Google Question is entirely different. It prompts you ask questions and one that knows how to disguise their question that leads to his own purpose does wonderfully well. https://questionhub.withgoogle.com/
I keep LinkedIn at next, Flipboard and FB in the end because most people do nothing but like your post without even opening the link. My best wishes, and nice day ahead.

I forgot to mention Stumbleupon which is another good one for quick publicity.