On a travel and lifestyle site I described Twitter this way: Twitter has a high barrier to entry and if you don't put in the time to figure out how best to use it, it just might be worthless.
For me it's a revelation and has absolutely changed my life in the year I've been using it for mindcasting. I'm now the #3 Twitterer in Istanbul!
I've virtually attended conferences around the world, gone to business school, gotten up to speed on my industry, and find *invaluable* the opportunity to connect trending thought across a slew of fields, learning and engaging alongside the top thinkers in innovation, healing, social media, sustainability, you name it.
If you're an intellectual Twitter is fabulous.