The subwoofer is by far the more interesting of the two. It’s called the Echo Sub, and it can work in conjunction with one or two other Echos to improve their sound quality. If you put two Echos in a room with the Echo Sub, the leaked listing says you’ll even be able to turn them into a 2.1 stereo system, with the standard Echos acting as left and right channels — something that isn’t currently possible. That’d help the Echo catch up to the HomePod, which already offers stereo pairing, though I do question the wisdom of purchasing multiple Echos for the same room to build out a speaker system.
The other item, the Amazon Smart Plug, looks like a fairly standard smart plug, capable of remotely cutting the power to whatever is plugged into it. Using the Alexa app, owners will be able to schedule routines, so you could set a lamp to turn on and off at certain times. The plug looks kind of large, but it also looks like the design could be specific to European outlets.
Amazon apparently had the Smart Plug listed at £95 (about $125 USD), which is almost certainly incorrect — these devices usually go for closer to $25. It also had the Echo Sub listed for £75 (about $99 USD), which seems plausible; but given how wrong the other appears to be, it should definitely not be taken as fact.
Pocket-lint says that both items had their release date listed as October 11th, which means we should know more soon. And certainly, it seems like new hardware from Amazon is imminent. CNBC reported yesterday that an Alexa-enabled microwave, in-car device, and more were in the works, with upward of eight new devices being released this year.