Can't wait for sprinting and food system. By iron bars, you mean like jail cell bars? I wonder if they are gonna fix how the Ghast shoots rapid fire, add a drop for killing a Ghast besides gun powder and are gonna extend everyone's world. Let me know if you can answer any of my wonders.
Its not guarenteed that it will generate. Might have to start a new world But Notch said that they are considering making the maps bigger so there is more room for things to generate.
i wish the next update added creative mode but i think the next update will just be a few bug fixes for the game in august. i think the pc features update will be probably during september and october. heres a good source for next update. http://www.minecraftforum.net/topic/1274802-mcxbla-title-update-change-logs-august-bug-fix/