As Twitter evangelist -- or Twitter boor, some may say -- in the Washington office I had just sat down with another victim.

I was just starting to explain to her how Twitter works when the following "tweet" popped up on Tweetdeck, the application I use to monitor Twitter.

"BULLETIN -- MICHAEL JACKSON TAKEN TO LOS ANGELES HOSPITAL IN CARDIAC ARREST, TMZ.COM REPORTS."

It was from BNO News, a Twitter feed which describes itself as "the fastest Twitter-based news service."

BNO News is indeed fast -- not always right -- but fast. A quick check showed TMZ were indeed reporting what BNO said they were.

I set off a mad scramble by informing the newsroom and my Twitter pupil bounded out of her chair saying "I need to call LA!" As it happens, Los Angeles bureau chief Rob Woollard subscribes to TMZ email alerts and was already on the case. But my Twitter pupil was impressed.

When she returned she said she didn't need any more persuading. "I'm convinced," she said. If only it was always so easy.