Twitter - A threat to push marketing?

I read an interesting article this week, asking if twitter is in fact a threat to traditional push marketing? I've pulled out an except below but recommend you read the linked article - ask yourself, what exactly is the best way for brands to use twitter?

''Meanwhile, a Twitter feed has become the latest must-have for brands wanting to seem up to the minute, or for targeting a young, tech-savvy market. And as with any new technology, its potential has quickly been seen by less savoury elements of society. Last month, New Media Age revealed that escort services and suppliers of drug paraphernalia, among others, had taken to using Twitter to promote themselves, at least partly because of a crackdown on such behaviour on Facebook.

At the moment, Twitter seems to be the latest example of marketers confusing form with content, the medium with the message. In the scramble to be seen to be using Twitter, the question of what it can actually deliver for the brand isn’t always being closely examined. It’s the same approach that led to marketers demanding virals, social networking applications and alternative-reality games when they first hit the headlines.''

Here's the full article