That is a broad question.
I love having an eReader because it lets me take so many books along with me. That way I can read whatever I have the whim to and not have to worry about bringing my library with me everywhere.
I also love the instant factor of eBooks. I can order a book and read it literally seconds later without leaving home. I also have been downloading a tone of free books so that is very appealing! Even used dead tree books usually cost a little. (just bought 3 softcovers for a dollar at the library sale) And the digital ones are easier to sort through, search, or just brows to see what is there....better than going through boxes and boxes of unsorted books...
Also, while I do love the feel and look of traditional books (well made ones...), I am an environmentalist at heart so I love that I can have fiction without killing trees. Unless a book becomes a favorite to keep in my library I give my books away...I just don't have space for more books.
As for MAKING eBooks I love to do it for fanfiction and online stories so I can take them away from the desktop with me and read them anywhere or anytime, even if the webpage suddenly disappears or is deleted. I also love showing the authors that just because the fic is digital doesn't mean it has to be just boring plain text. It can look like a well-typography-ed (sp??) book with images included.