Seems that nobody posted this yet.... We'll finally be able to see all legendaries in the game and their (hopefully) awesome stats!
You should be especially cautious on May 14, as with the installer unlocking and worldwide releases taking place, the entire game will be available to be discovered and datamined. We also plan to populate the Diablo3.com game guide with item data that Monday, which may themselves be spoilers. If you care about spoilers, it may just be best to not go on the internet on May 14.
Personally I don't care about spoilers from items, will want to see them as soon as they're up. And that will make the next 24 hours wait be more bearable...