Amazon Prime changing their price may have a negative impact on their numbers. As someone who received it as a gift, I already would not have paid the $79 previous price. $99 is not at all reasonable to me. It's easy enough to qualify to get the free Super Saver shipping, so if you don't utilize its other features, it's pretty much like throwing money out the window to be a member. Besides, it's not really free shipping when you're paying $99 upfront for the privilege. The higher the price goes, the more people will see this.
I haven't ordered anything from Amazon since they stopped offering free shipping on orders over $25, bumping it up to $35. We are considering an Amazon Prime membership given their free streaming library which we are currently checking out with the free trial. Price hikes will always influence membership levels, but if they're offering more, then they have a right to charge more.
Amazon Prime is a very valuable service if you purchase a lot from Amazon, but raising the price will decrease its membership for those people who don't see an overall benefit to the service. Customers must order enough from Amazon to more than cover the cost of membership in the savings on shipping and other services.
The price increase for an Amazon Prime membership will effect membership levels. Most people are cutting back on extra expenses and I think this will just be another expense that they can live without. I think it is a shame that once a service is going good that they go and increase the price.
The opposing side has mostly just said how Amazon Prime is unattractive, with which I agree, but I don't see how that would effect Amazon membership. It's simply annoying to see the constant promotions, but that's not enough to stop someone from using Amazon.Com. I don't care about Prime myself, and I am an Amazon customer, unaffected by Prime. Amazon Prime might actually slightly increase business, because of the benefits for the extremely impatient (which, besides the lavishly rich, are the Prime members).