Just had a message from G in my Adsense account saying I ought to sign up for this because I have multiple advertisers. The requirement for entry can't be that high because they will clearly accept me! My ad impressions vary from the high 6 figures a month up to the low 7 figures a month depending on the time of year.
n theory it all sounds good but I have concerns that G will be getting even more of an insight on what happens on my website than it does at the moment. But then again, because I don't have the knowledge to serve my own ads intelligently then someone will always have the overall picture be it G, Criteo or whoever.
It does seem, on the face of it, using Google Ad Exchange would allow me to use more than two ad networks which is good.
It would be great if a few who have used it posted their views so that those who haven't taken the plunge can get an idea of the upsides and downsides.