I know this thread is almost a year old, but this ability would definitely be a feature request from me. It's not too hard when there are only a few affiliates, but once that list starts getting long, it's going to be hard to figure out which ones are new.
Or, at least, if there was a way to sort them by the date they joined our program. Their registration date with EJ is there, but not helpful for this particular purpose.
I hope you'll consider adding one of these features - thanks!