Ad.ly - twitter spam marketing is the future
dotcoma.it
dotcoma.it
So you can unfollow.
Twitter are smarter than that. I think they will be more Hyper-targeted adverts that will be way more subtle than annoying. That's what I would be thinking about doing.
It occurred to me that maybe in a few years time we won't be googling for stuff by rather just "asking twitter" and automated bots/crawlers will respond based on where I am, what I asked for and details from my profile.
If twitter could bake in some kind of spam prevention (or reputation system?) it might just work.
That is something that Facebook have been teasing Google with for years, that they could be a better search engine because results would come based on your friends results.
I think this is very realistic reaction, people listen to the people they trust more than someone on I'm feeling Lucky. I'm basing my own startup on exactly that ethos.