Blizzard has released some nice details about the new Siege Tank on the Official StarCraft II site along with some great images and short videos. Dubbed the Crucio Siege Tank it will be key to any Terran players arsenal, just as before.
Going from the description on the site it obviously builds from the factory (just as before) and supports two different firing modules with twin 90mm cannons in assault mode, and a 120mm shock canon in siege mode, which is of course what it is famous for! It's specified role is armored support and mobile artillery, which is exactly where it was in the original StarCraft.
Going in depth of the description of this newly done siege tank is that there is a bigger emphasis on the assault mode being much more viable for combat. As an upgraded version of the old siege tank this is to be expect and it sounds like it may be able to go on the offensive a bit easier with little to no additional units supporting it as was needed in the original StarCraft. Here's the details:
In the first video you can see that the new siege tank easily takes on a force of six marines and a medic without any trouble. With the higher ground advantage still playing a big role it is obvious that positioning will once again be key to the units success. Looks like the siege tank will be just as awesome as before!
Links
StarCraft II - Source