Jens Bergensten has announced on Mojang’s website the features of the new Redstone Update, which is available now in pre-release form.
Here are just a few of the new additions, straight from Bergensten’s post:
Added Redstone Comparator (used in Redstone logic)
Added Hopper (collects items and moves them to containers)
Added Dropper (similar to Dispensers, but always drops the item)
Added Activator Rail (activates TNT Minecarts)
Added Daylight Sensor
Added Trapped Chest
Added Weighed Pressure Plate
Added Block of Redstone
Added Nether Brick (item)
Added Nether Quartz and ore
Added Block of Quartz, with half blocks and chiseled variants
You can find a full list of the added features and the pre-release on Mojang’s website. The update will be officially released March 13.