Augmented Reality has the power to accelerate the pace at which sales of physical goods, especially homewares and some apparel, move online. It's also much more important for this sector than 'full fat' Virtual Reality. The ability of AR to place a product (or multiple products) in a customers own context gives direct-to-consumer sellers a distinctive proposition, beyond just convenience, to compete with physical 'touch and feel' stores. In a way, it's literally the first 'killer app' of the next generation of ecommerce in that the customer just needs a phone with a camera.
When will this start to appear in the mainstream? It's already happening - I'm involved in 2 client AR projects and Shopify (supporting thousands of merchant stores) are developing tools right now. In certain product sectors, I expect to see AR being commonplace within 3 years. For a sector like furniture, with nearly 80% of sales still offline, the introduction of the ability to place chairs virtually in the room you're in and change colours, styles, etc. is likely to be profound.
In fact, just a couple of days after I first published this post, furnishing giant Wayfair announced the piloting of AR advertising in a partnership with Facebook.