This is a hoax, this is not true, but it spread around the internet over the weekend and I found it pretty funny. Again, this is a comic, who did a skit of some sort. Microsoft confirmed this is not a real employee or ex-employee at Microsoft.
The video portrays a disgruntled ex-Microsoft employee describing how he was fired by Microsoft's CEO, Steve Ballmer, over not saying "Bing" with enthusiasm.
If you know the jokes about Ballmer, this is pretty funny.
Forum discussion at DigitalPoint Forums.