Question About The Difference Between CPV and Media Buys

If by CPV you mean contextual traffic through adware (such as trafficvance, adon, and other CPV networks) then there is a fair bit of difference.

CPV traffic in that sense is traffic that your pay anywhere from 0.01 to maybe $1 for each keyword or URL that you target your ad to appear on when the user of the adware application enters that keyword or URL. You can also execute Run of Network ads where you pay a certain dollar amount for your ad to be displayed to all the users in the adware network. Now the problem with this traffic is that the user base is quite small (around 10 - 30 million). However it is highly targeted if you know what you're doing.

Online Media buys on the other hand are where you can buy a virtually unlimited amount of ad impressions / views across various websites, newsletters, and other online media. This is what the big guys use, and generally the cost is higher (not as much as most think, but still quite high), and if you dont know what you're doing you can lose all your investment in a matter of hours. However, it is the most sustainable traffic source out there and the amount of traffic can almost never be exhausted.

Anyhow, thats a small primer on the two forms of traffic. Hope this helps.