I expect current style ebook readers will be as defunct as Betamax in a very few years.
Luckily we aren't paying $1500 a pop in 1975 dollars.
I love my Sony Prs-600 but will be shopping for something better as soon as I am back in a town with more than one store
A 10% better display or better menu navigation will do it for me.
But wishes for improvement aside, we are all lucky to be in a brief period of time where the technology is not wide spread. This enables easy sale of our current e-readers when we wish to upgrade or they are appreciated gifts to family members.
Until very recently I was the only person I know who actually had an e-reader, and the one I know now bought one because they saw mine. And many of my friends are pretty tech savvy and gadget oriented.