A few nights ago, author Michael Dahl entertained a group of youngsters wearing their Batjammies at Alexandria's Hooray for Books. Dahl put on his own set and then read the book he wrote that is illustrated by Ethen Beavers. Dahl's story draws a parallel between a young boy getting ready for bed and Batman heading out to fight crime. Beavers did an excellent job with the Batman Adventures animation style. The book is aimed at the very young, and the children in the crowd certainly enjoyed it. Full disclosure - I was the only adult there without young children.
Dahl's next book is Good Morning, Superman, but some children starting reading it so I didn't get a glimpse. It's by a different artist though.
And they have autographed Wimpy Kid books for sale still.