The official information about the upcoming New Magincia Bazaar, which has been renamed the Magincia Encampments, was released a few days ago.
Keep in mind that this maybe a part of the upcoming booster packs and some if it might require the purchase of one or both booster packs. That is subject to change. Language within the client files indicates it will require the purchase of a booster pack.
Here’s a brief bit of information from the PDF (which UO Guide assembled into an online guide):
The New Magincia Bazaar is a dynamic new center for commerce that offers buyers and sellers alike the opportunity to trade in extraordinary new ways.
The Bazaar of New Magincia consists of 50 stalls that will be leased for one week at a time by prospective merchants. These stalls are available to renters for commerce. The Bazaar Authority keeps expert brokers on staff, who are available for hire by those leasing stalls in the bazaar. These brokers act on behalf of the stall renter to buy and sell merchandise. Brokers are of two types: Animal Brokers, and Commodity Brokers.
Animal Brokers will take possession of pets and sell them at a price determined by the owner, charging a small commission for each sale, plus a small percentage commission on the sale price of unsold inventory. Prospective customers will be able to preview animals for sale in specially designed pens, and see their vital stats.
Commodity Brokers are able to both buy and sell commodity items for their employer. They work on commission similarly to Animal Brokers: they receive a small percentage of each purchase or sale, and they charge a percentage commission on all sale-able inventory.
I would highly recommend visiting the UO Guide page linked above, as it’s the easiest way to view the information online. I’m not going to restate the information here, although I’ve posted several stories in the past about it.