This book is an update of the previous editions of the "Letters to Shareholders" book. It includes the most recent letter, giving the book 50 letters and 769 pages in total.
The version sold at the meeting is a limited "50th Anniversary" hardcover edition. The cover is a dust-jacket-less midnight black with gold embossing. It looks quite good on a bookshelf. There will only be 1,000 copies printed due to the hardcover cost and limited demand, and as such each copy will be about 2x the price of the original.
At the meeting, the discounted shareholder price will be $37.33. Any copies not sold at the meeting will be sold online (from this site) for $49.
After both this and the 2013 editions sells out, later this year Explorist will release a print-on-demand version (paperback, slightly lower quality paper, more time to deliver) that anyone will be able to purchase from then on. As always, the Kindle edition of the book is also available for $2.99, updated annually.*
* Update (November, 2015): The limited hardcover edition is currently sold out. See here for the print-to-order hardcover edition.