Actually - looking more and more at their website I'm convinced it's these guys (Netcompartners). They 'partner' with media companies to put out content and share the revenue... So, basically they don't do anything (what kind of media company would be naive enough to share their revenue with a made-up company that doesn't produce anything). Most of their 'partners' are Russian channels (which already raises flags) and their contact address is in Switzerland (couldn't locate it on google maps).
So, as many suspected, I think they set up this channel to make false claims on people's content so that they could simply steal their revenue by putting ads on it.
That's why they are targeting many people who put up video games (perhaps on the false belief that they won't defend their work which contains 3rd party content - though, this is technically legal since you are doing a review etc).
My work is totally my own and doesn't contain anything owned by anyone but me - so I don't know why I was targeted. Pity I lost a lot of revenue since my ads were taken down... but 'easy come easy go'. Without Youtube I wouldn't have any revenue from my videos and I guess I'm trusting they'll sort this out.