During their latest quarterly results conference call, Amazon revealed that they are considering the possibility of raising the price of their annual Prime membership by $20 to $40 to cover increased costs of the service. The current Prime service includes free 2-day shipping, plus a streaming video library, plus a free e-book rental per month, plus a free Kindle First new e-book release per month. If you follow the news, both shipment costs and video content costs are rising. They did not give further details whether they plan to create multiple tiers, for example, some people only want the free 2-day shipping and don't care for the video/e-book features.
This is not an official announcement of a price increase, but if they mentioned it during their conference call, they are probably preparing the ground for it. As of the time of writing, the Amazon Prime membership remains $79 for 12 months for new subscribers and renewals. If there is a price increase, it will affect future renewals and future new members. They currently offer a 30-day free trial, so if you are on the fence on this service, this may be something to consider.
We've already seen Amazon make adjustments to counter the increasing costs of shipping. They created the Add-On program (some sub-$5 items are not eligible for free 2-day shipping for Prime members unless they are part of an order of $25+) and increased the free Super Saver shipping threshold from $25 to $35 for non-Prime members. Also, some heavier and more-expensive-to-ship items now may cost more than $4 if you select 1-day shipping as a Prime member.