The effect is not that bad, however.
That doesn't change what I said in the slightest. Blockland doesn't use Voxels. Also, the only thing casting shadows in minecraft are the blocks. This also means shadows are only calculated when there's a block or lighting change. Where with Blockland, it's calculated in real-time.
Edit: And one final note, the sun always lights straight down in Minecraft despite that it moves. Where the sun in Blockland has dynamic angles.