Pistons

[bluenovajinx]

Pistons do not seem to push or certain blocks like they do in Vanilla Minecraft. This doesn't seem to be an intentional feature from what I can tell.
The following ores are supposed to be moveable, but at the moment cannot.

Iron Ore
Gold Ore
Lapis Lazuli Ore
Coal Ore

Oddly enough Redstone Ore correctly moves.
Similarly the following solid blocks are glitched

Block of Iron
Block of Gold
Block of Diamond

The Lapis Lazuli Block remains unglitched.
All other blocks seem to act normally (spawner, obsidian, ovens are not supposed to move.)
I was a bit surprised that the dungeon blocks move correctly, but of course they cannot be pushed in an actual dungeon.

[Handyman]

uhm... first of all what kind of pistons are those?
If they are sticky then what you say is correct,
If they are non sticky then you mean the other way arround?

The fact that most ores cant be moved is because of duping.
Since it is possible to get these ore (and diamondore not to forget) you could place the, again, move them with a piston and it would be a whole new ore, which will give you new ore blocks again (with silktouch)

[bluenovajinx]

Yes, they are all sticky pistons

Okay that makes sense. If a block is pushed with a piston, McMMO might see it as fresh and possibly give you multiple ores again. Is this also the case with solid blocks? Solid blocks of Iron especially make for nice piston doors. Pistons used to do some strange things, but seem more stable in 1.3, I know the block id transmuter no longer works for sure. Do you know if the solid blocks of iron and such do not push or pull because of a conflict with McMMO or because of a dupe bug with the pistons themselves which has been fixed? It seems unlikely that McMMO would give multiple blocks for breaking crafted blocks that are obviously not naturally occurring, but I've seen people code much dumber things.

~bluenovajinx

[Handyman]

that solid blocks cant be moved is because of theft