Here’s some Zerg video clips I found from ThisIsGame.com demonstrating the Zerg in action! Check them out:

Personally the Zerg was my favorite race in the original Starcraft and I’m definitely looking forward to seeing some more Zerg!

The long awaited Zerg have been revealed over at the official Starcraft 2 site! Here’s some of the preliminary information: (thanks to Starcraft-Source.com)
Units:
Roaches

Very fast speed + high regeneration rate
Absorbs lot of damage so without focus fire on this unit, it won’t be easily killed

Overload:

Creates creep, more special abilities are added, slow […]

A screenshot of what appears to be a Zerg Ultralisk made an appearance in Rob Pardo’s power point presentation at Blizzard’s GDC ‘08 presentation. Check it out:

(Click to Enlarge)