| As others have posted to some degree residential bandwidth is a chicken and egg proposition, until a large portion of the population has higher speed services are not going to be developed to take advantage of the speed.|
That being said we are getting to "good enough" speed for lots of people. HDTV takes about 15Mbps per channel in MPEG2, about half that in MPEG4. Cloud apps are bandied about as huge consumers of bandwidth but by an large the user's computer/smart phone becomes little more then a glorified terminal with the heavy lifting being performed in the cloud.
More is better but I'd be hard pressed to argue that 50Mbps is not "good enough" for the near term. To me a much more important issue is delivering multi-megabit speed to the entire population, not worry about whether 25, 50, 100 or Gig was fast enough for the lucky few.