The article is actually misleading. It's not the WWW that was born on Christmas 1990 - it was the first edition of the WorldWideWeb browser that was released exactly 20 years ago.

References: - http://www.w3.org/People/Berners-Lee/WorldWideWeb

Interesting stuff: WorldWideWeb (the browser) was written in Objective-C on a NeXT computer by Tim Berners-Lee himself.