IGN has posted a full 21 minute video of gameplay in Starcraft 2: Wings of Liberty. The battle features Terran vs. Protoss and gives a decent look at some of the new units and abilities.

You can see that video here.

One of the abilities I was intrigued by was that a newly built command center was able to carry 4 SCVs with it to immediately start mining at the expansion base. Another new feature shown was not only the ability to traverse terrain at different levels with certain units, but also that some parts of the terrain could be interacted with, in this case a pile of boulders blocking/protecting the entrance to an expansion site. They were also pretty quick to point out that this is still an alpha version and you can probably bet on a somewhat lengthy beta version to work out all the bugs. That being said, things are looking very good so far.