It depends on how much they follow the design of the original piston mod.
In the mod, you can "stack" pistons on top of each other so that they can indeed become an elevator (especially the "sticky" pistons). That can at least create a "lift" to create something like an "elevator" moving from one floor to another.
As to how this will actually work... we won't know until it is actually put into the game.
I don't know...maybe because Mojang has stated that all modifications to their original work is, by law, free for them to use, modify, distribute and ultimately profit off of without giving any credit whatsoever to the original creators? That seems to be a very strong reason, since every Minecraft mod that other people have come up with are, technically speaking, inspired by Mojang's work.
That is the licensing terms under which Mojang has agreed to permit open discussion of mods and for posting in these forums, of which the original "Piston mod" was certainly treated as.
In terms of copyright law, you had better be a whole lot more careful about stuff like this. Particularly in Europe, copyright laws are pretty stiff in terms of giving recognition to the original creator, so it certainly might be a good idea to at least do some sort of Kudos to others who might have inspired the design. Such copyright can't be surrendered, and all that would ultimately mean is that if a mod maker wanted to be an ass about this issue, they could "force" Mojang to simply not adopt the mod into the game itself.
Derivative copyright laws are real tricky things, although in this case the "common sense" thing is to not get into a big huff about it. The fact is that pistons are being incorporated into the game due to their popularity and the fact that such an idea has some significant ability to expand the game in some big ways. Becoming an ass about who gets credit for something like this is of secondary importance at best.
Still, even if it isn't strictly required legally, it might not be a bad thing to at least acknowledge the modding community in this case, even if the actual implementation is more of a full rewrite of the idea.
I can see some very MEAN Adventure maps being made with these...Combine with the signs holding something up no matter what, it can be used for some nasty tricks... you hit a Pressure Plate, BOING up goes your little Block, and you, up into a ceiling made of Magma...
Rollback Post to RevisionRollBack
*build giant castle of cobblestone* * Choses to live in the mine itself*
*Sees Enderman, Pulls out Blaze Rod, and charges*
What is REALLY exciting that no one has pointed out yet is that when in their unexpanded form, they are 1 block the pistons face doesn’t intrude into the next block over, which is different from the mod. This means that almost definitely water can pass through them
Jeb will be adding "sticky" pistons too. But he's leaning towards them being "sticky" by having them be sharp and spiky rather than using glue or slime. Perhaps because slimes can be so hard to find, I know I still have never seen one.