Top priority:

• Separate mode from creative
• Allow player to select mode upon world creation
• Disallow commands without cheats
• Per-player modes (stored on the server)

Additions needed (in order of priority)

• Disable creative menu for survival players
• Block Breaking
• Item collection
• Liquid physics
• Misc. physics (crouching, ice, etc)
• Health/Damage calculation
• Damage types
• Fall damage
• Hunger meter (?)
• Eating
• Regeneration (?)
• Defense stat/calculation

Issues relating to the addition of Survival Mode:

• Procedural Crafting (Remaining Work) #89
• Rework pickaxe power/time to break a block #232
• Stamina #257
• Particles #293
• Armor and accessories #604
• Calculate time to break a block from tool properties in survival and add a block breaking animation. #620

Entity related:

• Entity AI #86
• Entity Animation #87
• Entity Support #88
• Make it illegal to place blocks inside of the hitbox of entities #90

Physics related:

• Friction and Air resistance #83
• Buoyancy #84
• Swimming #85
• Make the player coordinates wrap around at the integer limit #310
• Reduce friction for smoother movement #553
• Crouching & Crawling #561

Inventory related:

• Allow blocks that store items. #78
• Improve how the inventory is synchronized with the server #643
• Item drops cannot be collected #644
• Breaking blocks doesn't drop items #645
• Improve how block placing/breaking is synchronized with the server #751

Implementation Bugs:

• The creative inventory remains open and items can be taken from it when the game mode is switched to survival. #743