I've never been a big fan of Twitter. I can see the value for those hyper-connected individuals who rely on social networks to secure or build awareness or notoriety, but based on my ten years of experience designing, developing and promoting websites on the Internet, I wholeheartedly believe that Twitter is in its final days.
It might be hip to be social, but TWitter is little more than a technology platform, a conduit to "get things done". The problem is that When you enable someone to do something (like be social) chances are good that you are going to be taken advantage of - and that is precisely what is happening right now at TWitter.
Steve Rubel at MicroPersuasion blogged recently about Adjix, a URL shortener that wraps the page you are linking to in your tweets and frames it in advertising. I've known for months that once hard-core super-affiliates figured out how to leverage Twitter, the game would be up. This is only the first of these services - many more will appear, diminishing the credibility of that platform as a legitimate service.
Twitter is not sitting around doing nothing however. They are taking proactive measures now to reduce spam by suspending accounts when spam is spotted, starting factoring in feedback to address spam issues more quickly and have personnel dedicated exclusively to the problem. But in my opinion these actions are ultimately band-aids to a larger, more sinister underlying problem. When you spend your resources scaling your services while continue and build awareness with the broader Web community, you miss out on developing new ways to do what you do (and more importantly need to do) better.
That's why these are the final days of Twitter.