Would you like to know how much the revenue for ebooks in the US the first quarter of 2008 is?
I can tell you:
2008 Q1 - over 10 million USD.
2006 Q1 - 4 million USD
2004 Q1 - 1,8 USD
For the last 4 years, the sale has more than doubled.
Now - this is something publishers should think about!
Source:
http://www.openebook.org/doc_library/industrystats.htm