What is it with the increase in use with global postbacks? This is where you send the network an id and they send it back to you if it converts. It seems that some affiliates are actually using this type of tracking and optimising on a single tracking system.
The best way for a network to do conversion tracking is to place a image/iframe pixel for their affiliates. This lets the more technical affiliates do all sorts of things to help them optimise campaigns.
It’s impossible even to do simple things like placing retargeting pixels using a postback conversion pixel because the code is loaded from the networks servers rather than from the end users computer.
An iframe conversion pixel allows you to package all the networks pixels, your tracking pixels, retargeting pixels and anything else you need in to one single line of code. This can then be modified by the affiliate without having to wait for the network to place/modify another pixel.
Also if you host the conversion iframe on the same domain as your landing page you can check for cookies which have been placed when the landing page was viewed. This is great for MV testing, storing stats and user data. Affiliates can then leverage that data to improve their campaigns which ultimately works out better for them and the network.
This is performance marketing not amateur hour, postback pixels are not good enough and should not be accepted as the norm!