BlizzCon Ends 
So after playing the SC2 demo many many times BlizzCon closed it's doors. Here's a recap of the new SC2 information released.
SC2 Demo:
The Terran race has finally been shown off, and has changed drastically from how it worked in SC1. It took me quite a few games with the Terran to figure out how to be effective with them. With new ways of building units lots of new buildings and many of the upgrades moved around. Many core units like the science vessel gone and turrets not detecting anymore all took some time to get used to. In contrast the Protoss felt very familiar most of the buildings remain unchanged, and the tech progression is similar. I can't squeeze all the details into a news post but check this
thread for detailed information about the Terran and Protoss from the demo.
Single Player Campaign:
The new single player campaign sounds very intriguing. Instead of a briefing room you get to hang out on a battlecruiser in the Terran campaign. You will play as Jim Raynor and be able to interact with people on the ship. There will be several sub plots with various members of your crew some unlocking new campaigns, some just opening more story-line/lore for you to enjoy.
The mission system will be very open ended you will be able to choose which missions you want to go on and even skip some missions. You will also earn money from completing your missions which will allow you to purchase upgrades for your army. Like unlocking the viking unit.
Rob Pardo also touched on the other two race's single player campaigns and said that like the races themselves the single-player campaigns will be very different. Stating that it wouldn't make sense to be able to purchase upgrades from a vendor if you were a Zerg. Each races single player experience will be very different.
Other Tidbits:
They said that SC2 battle.net would be an evolution of the WC3 battle.net and hopefully will make as big of a jump in terms of features from wc3 to sc2 as they did from sc1 to wc3.
The map editor is supposed to be an upgraded version of the WC3 editor. But he cannot confirm if the new editor will be able to create campaigns or if it will continue to be just a map editor. However he said it is something they would like to do.
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That's all the major info from the stage demo you can watch it yourself at GameSpot who was allowed to setup video cameras for the demo.
Related Links:
http://www.blizzcon.com