Okay then here comes why I said that I think the so called 'high CPM' values are nothing more than a good story to lure people into a network and share some of their revenue. I'm partnered with just Adsense alone, not a network partner. I make English videos on music production, while I'm based in the Netherlands and I'm getting most of my views from the US and UK.
So with that explained I just looked through my Analytics and I started 2013 with a CPM of $3.19 on January 1, while at the 9th of January this year my CPM had already gone up to $10.59. Ever since that 9th day of January up until the last date of this year that is currently in my statistics I haven't dropped below the $10 CPM mark. In fact, it has been rising ever since January. From March till halfway through June I maintained a steady CPM of $20 with a little sign of growth, but then from the second half of June till August my CPM has been going up and down between $20 and $35. Also the closer I go to the month August the more days are showing CPMs above $30, so during that time it was still growing. After August my CPM dropped, but that is logical since in August I ended my last series of tutorial videos, but even though my CPM from August till the start of September have not dropped below $20. I can now actually see a big growth again ever since I started uploading more music, and my CPM has had a minimum value of $20.56 and maximum value of $54.15 during the month September. So why is what I said in my post not totally accurate?
Then to the 'premium' ads... Networks try to get advertisers to put big money in their network, and they will try to link these ads to your channel and reward you with a higher CPM, but that is exactly what the Adsense program already does for you, although it is the advertisers themselves who can specify a particular niche of channels they want their higher CPM ads to display on. So naturally, if your content is good and your channel is growing you also grow the chance to get higher paying ads. No advertiser will ask for their ads to be displayed on a channel with little to no views, but when you stick out and show that your channel is good it will all come naturally.
Good content is THE KEY to generating more revenue.
(Also as a side note, the past year has also been the year where my channel has grown a lot, and the CPM has grown with it)