I wonder whether there will be a division of labour on most servers. I can see it happening on RP servers but why would a player decide to have nothing to do with a large chunk of the game? Even if I mostly just ran a farm I'd want to go down into the caverns anyway meaning I wouldn't need to trade my food for metals. Players don't get better at any of the tasks in game and no task is all that complex so there is little reason to pick a single profession.
I can imagine, on friendly or private servers, group stockpiles of excess stone, dirt, wood etc and small trades of goods or favours.
It has to be the first time I've been for adding some limited skill progression to a game, usually I detest grinding. Ideally the skill levels would be capped to avoid god players. You'd slowly get better at whatever you naturally did. Skill would impact actions or the effects of crafted items. Well crafted food would heal more, tools / weapons / armour last longer, weapons deal more damage etc. Anyone should still be able to make acceptable tools but the skilled would have a small advantage but more to loose. When you die you loose the skills. I don't know if it would work, hopefully moddable servers will let us find out.
Is anyone else excited about scriptable servers with custom tilesets?
I'd quite like to see a server where you need to eat and drink, proper survival.
I'd still argue strongly against grinding, skill progression, etc. One of Minecraft's charms is the idea that you
can do everything.
Personally, I'd say that you could increase specialization in a few other ways that don't add grindy elements:
* Biomes. For instance, clay is currently ultra-rare. If some biome existed where clay was abundant, then people in other biomes would end up trading for it - it'd be a real pain to sail halfway across the known map just to mine a few clay blocks. Likewise for other items; a massive desert might not have any trees. A mountain range might have more iron than your average plain. And so on. Not only would this encourage players to trade, it would also give us 'trade routes' and the like for free. (
Fake edit: looking back over my other suggestions, this one really seems like the best. As in, this is the only one that would really work well. )
* Teamwork. Mining is already going this way - once creature spawns are present in the underground, mining with a bodyguard will be far safer. I'm assuming that monster spawn numbers will be somehow scaled to player population (the number of mobs that threaten one person in single-player would be boring on a server with 20 players), and so you'd probably want someone watching your back while you're mining.
If you need support to perform a task, trading suddenly becomes valuable. Normally, it's a total pain to find someone with a given specialty and organize a trade with them; if harvesting the resource on your own is equally challenging to organize, trading might become more valuable.
Of course, not every job needs a bodyguard, and I'm having a tough time figuring out how farmers and whatnot would 'team up', but the concept is at least solid - if mining the depths of a cavern was a non-trivial problem that generally required multiple people, a non-miner would be tempted to trade rather than go mining himself.
* Limited inventory space. I'm having a tough time suggesting this... but if your inventory space was more limited, trading might become more important. Again, it's an issue of adding more time demands to 'switching jobs' - if you can't carry around the tools and blocks needed for
every job on the planet, it's a hassle to switch them up. If a woodcutter needs to dump all his wood and axes into storage before setting off into the bowels of the earth to mine, he might be encouraged to trade with a miner for the extra iron. Especially prevalent if chests can be broken into - you might come back from your mining sojourn to find your woodcutting tools stolen! If you'd asked that miner to trade for his iron ore, however, then your tools never would have to leave your inventory, keeping them safe.
...huh. All my suggestions seem to be ways to annoy people and add useless effort to the game... which, frankly, is basically the same as grinding. I still like the biome suggestion, though!