Per MWT's tumblr, here are the details:
http://meganwhalenturner.tumblr.com/post/160080056447/the-very-nice-people-at-barnes-noble-at-market

"The very nice people at Barnes & Noble at Market Commons said it’s okay if we come hang out in their store for a while on Thursday night, May 4th. This isn’t an official signing. Just a meet up. Bring books if you’d like me to sign them, but please be prepared to buy a book from the store as a thank you to them for hosting us. And if you can let me know you’re coming so that I can give them a estimated head count, that would be great."
http://meganwhalenturner.tumblr.com/post/160080056447/the-very-nice-people-at-barnes-noble-at-market

"The very nice people at Barnes & Noble at Market Commons said it’s okay if we come hang out in their store for a while on Thursday night, May 4th. This isn’t an official signing. Just a meet up. Bring books if you’d like me to sign them, but please be prepared to buy a book from the store as a thank you to them for hosting us. And if you can let me know you’re coming so that I can give them a estimated head count, that would be great."