Nobody anymore. --- I spend a lot of time on youtube. I watch a lot of vids about all sorts of topics I'm interested in and I'm sub'd to ~200 channels.... Vape vids, though: I sub to a guy (cutlerylover) who does knife and gear reviews who also happens to occasionally do a vape review. And, I've been subscribed to another guy (SuperXDrifter) for a few months who does rebuildable tutorials even though I only decided to use a rebuildable a few days ago... because he's really active on ECF and his vids are informative. I like to support those who support the same community I'm part of.
Most of the more "famous" reviewers were at one time or another really active on ECF and VapersForum etc (yup. pbusardo used to be a regular poster on ECF and GrimmGreen was on vpaers forum what seemed like 20 hours a day for a while... etc etc etc. Almost any vape vid name you'd recognize was at one time or another active on the forums)... I tended to give their youtube channels some loyalty when I felt like they were really active forum community members. It seems like most of them end up abandoning the forums for whatever reason. So, then I tend to not feel so compelled to support their youtube channels by watching vids, letting the advertizing play, and clicking the like button... It's not anything personal or anything like that - I just don't feel as compelled when they are no longer contributing to the forum medium.
Another part of my loss of interest in vape vids is the fact I lost interest in new gear. I used to know pretty much every thing there was to know about every device and could spout specs and details about pretty much anything anyone might ask a question about.... Those days are gone. I found what I like a long time ago. Until last week, I hadn't bought a new PV since April 2012, and the one I just got wasn't because I needed it. The one I've been using for the last two years works perfectly. The new one is pretty much the same type and is from the same vendor... I just wanted it, not because it's all that different than my others, but because it's so much the same.
I think it's likely I'll continue the same behavior. If someone who is active on the forums does vape vids, I'll support their channel. If someone I watch for other content gets in to vaping and does occasional vape vids, I'll be happy to watch, let ads run, and click like.