[jeresig]

They're narrated by Jessica Liu, more details here: http://ejohn.org/blog/introducing-khan-cs/

[eranation]

Jessica is doing a great job as well... :)

she sounds a lot like Vi, and this comment on this one, 5 seconds from the start helped my confusion...

http://www.khanacademy.org/cs/1-welcome-to-codecanvas/882454...