checkout the sc2 gameplay videos, its roughly 19-20 minutes in total.
well theres 3 versions of the gameplay videos, they have different quality.
1- no music, no explanations, no crowd
2- no crowd
3- everything.
1- no explanation by designer:
-this is like the above massive battle video (doesnt have music like the above link).
http://www.youtube.com/watch?v=bXpLQUVy6rU&mode=user&search=
-nearly the full thing, no explanation/music, and is missing the stuff in the link just above this.
part 1
http://youtube.com/watch?v=l_G-0q2HAwE&mode=user&search=
part 2
http://youtube.com/watch?v=zdagKd2t1Sc&mode=user&search=
2- explanation, but no background crowd.
decent quality ones added by haply, the whole thing in 2 parts
http://www.youtube.com/watch?v=H6IhMdgdFvQ
http://www.youtube.com/watch?v=CCleQxk3vsg
3- explanation and background crowd cheering.
random fight between terran and protoss with really nice nuke ending and zerg at the end

http://www.youtube.com/watch?v=Sog2k6s7xVQ&mode=user&search=
introduction to many of the new units:
The explanation of the units is in english (one of the designers of sc2 I think), while the rest of the stuff is in korean(fonts, unit speech)
part 1
http://www.youtube.com/watch?v=aJDFw4TGWmo&mode=user&search=
part 2
http://www.youtube.com/watch?v=_TR7nGISEfc&NR
last part of units
part 3 of units, this doesnt have the crowd in the background
http://youtube.com/watch?v=x59E-83pI8s
ps: im meza in the other forum(if you saw that post) => Im not copying another persons post, just coping the one I posted on the wow forum.