Starting with Nauctis next year:

• 1/1000 regular boosters will be a "God Pack" (all rares/mythics)
• 1/300 Collector boosters will be a God Pack
• Japan Showcase cards can now be found in regular packs
• Increased odds for foil Rares/Mythics
• Play booster packs are renamed to just booster packs
• No more foil commons or uncommons in regular boosters
• No longer a guaranteed foil in every pack
• Collector boosters removing 2 commons and 1 uncommon from the foil slots