What effect will the ever increasing Pre Paid Credit Cards have ?

I think it depends what you compare them with.

Comparing pre-paid and normal credit-cards isn't altogether appropriate, I suggest, because most (I won't say "all") people with only pre-paid credit-cards are not able to get normal ones, for a variety of reasons which also vary quite a lot from country to country.

Credit-card processors who take pre-paid credit card payments (and that's most of them - few seem to distinguish) do take them for rebill products. But if someone doesn't have the money on their card at rebill time, they're only really in the same position as someone whose normal credit-card is declined at rebill time. It may be that someone who has only a pre-paid card in the first place is more likely not to fulfil their rebill, but the principle's the same, really.

I think the point is that as vendors and affiliates, we're getting something extra from such customers, anyway: if they didn't have their pre-paid credit-card, they probably wouldn't have one at all. So to me, it feels appropriate to compare "someone being a potential customer" with "someone not being a potential customer", and I'm glad such things exist.

There are also people who wouldn't buy things online (or at least only for big names that they trust!) unless they can use a pre-pay card. One of my sets of parents is like this, before they make an online purchase they transfer money onto that card and then make the purchase.

It is a trust issue - some people are wary of online retailers, and a lot of people are also wary of sneaky re-bills.

I'm with Alexa - pre paid cards actually offer a chance for more sales.