One thing that would really help such scenario become an affordable reality, is seeing the cost of living rapidly decline for people living with low wages.
For them , the major living expenses are housing, healthcare, food and energy, and a car(when there's no decent public transportation).
Those areas mostly doesn't see big cost reductions. Some of it is because high barriers to entry, regulation, dislike of low-end disruptive innovation by people(in healthcare and probably in housing), low investment in r&d (in construction) and other reasons.
On the other hand, if you look at the third world, those are exactly the ares they out innovate the west:
1. low cost housing(Tatas to build world's cheapest home for Euro 500[1], cost of residential buildings made with reinforced concrete to average of less than 1,500 yuan($235) / square meter[2])
2. low cost healthcare(Dr. shetty, reducing the cost of heart surgery to $2000 and working towards $800[3], program that trains lay people to treat depression in india[4] , and many many others)
3. low cost transportation : the famous TATA nano.
4. while u.s. is really innovative in this field, china is probably leading this field throught huge investments and low labor costs.
So this leads to an interesting situation: In 20 years , when automation might take hold(here and in the third world), who will be better prepared for it?
[1]http://news.ycombinator.com/item?id=2770956
[2]http://nextbigfuture.com/2011/01/45-more-buildings-to-follow...
[3]http://articles.cnn.com/2011-04-06/world/india.health.cities...
[4]http://www.nytimes.com/2008/03/11/world/asia/11iht-depress.1...