I also bought my reader due to poor vision, and I've been busy reading ever since (only two months or so now, but lots and lots of reading).
You might enjoy the Vorkosigan series by Lois McMaster Bujold over at Baen (
http://www.baen.com/author_catalog.asp?author=lmbujold). It's science fiction with lots of action but also well-drawn and very human characters. She often had me smiling, giggling, or outright howling in laughter with one character's antics, in particular. The author seems to have a rather dry sense of humor -- just using the phrasing of a character's dialog or the minimal but effective description of something.
I just wish more of her books were in ebook format.