At its core, this mod adds a new key-binding for simple block rotation. If they key (Ctrl by default) is held down while placing a block, the block will be oriented in an alternate way. If the key is held down while right-clicking a block, the block will rotate horizontally.
Also added is the ability to place slabs vertically (by rotating normal slabs) along with two new slab-types (nether brick and moss stone). Lastly the mod revamps log placement: logs will be placed upright by default (identical to pre-1.3), and will only be placed on their side when rotated placement is used.
For 1.4.7/1.4.6 (Only Modloader version)
Modloader version: http://www.dl.9minecraft.net/index.php?act=dl&id=1355051666