ePiracy is scary, but it's not just ebooks being shared. They can make digital copies of print books in a matter of minutes. My author friends find their books shared on the day of release. I know one author who quit writing one series because the books had been pirated so much she wasn't earning enough to be worth her while.
As for ebooks, they are all I read now. I only buy paper when I'm at a signing. Most people who have a good ereader end up preferring the format once they adjust to not holding a book.