I have seen numerous articles about whether or not Twitter is going to make it. I am thinking, "How can it not make it?" Unless they do something incredibly stupid and alienating, they cannot help but succeed. Let me tell you why.
Look at this Blog ... Kinda sparse, huh? Postings a bit irregular and not very consistent. It takes a lot more time and effort to maintain and keep a full fledged blog up than I have. Micro-blogging on the other hand is quick and easy. Most people, especially anyone with a spouse and kids, do not have the cycles to spend writing lengthy tomes on their blog.
Twitter on the other hand, allows anyone to make a quick observation about something they read, learn, hear, or do. It can enable a large segment of the population to express themselves and their opinions about anything that matters to them. It could especially appeal to all the SMS text users, who are used to constant, shorthand, streaming communications. Twitter is your life in motion.
I also love the fact that I can post on Twitter, and have that information automatically cross-posted to one or more of several social media sites. I want to duplicate effort as little as possible. My spouse complains that I already spend too much time in front of the computer.
The only real problem Twitter has is that they have not figured out a way to fully monetize the service. This is a slippery slope and they have to tread lightly. Something I would consider is maybe partnering with Google and taking advantage of the AdWords/AdSense programs they have. Google is definitely the master of non-invasive advertising.
Another possible route is to create premium services that can be added on. Fortunately or unfortunately, some of the areas where this could be profitable are being filled by 3rd party developers. For example using Twitter for job searches, or for sharing pictures.
Maybe they can market Twitter to corporations for internal use. All the employees in a department or group could follow each other and always know where each member is on various projects. This is another niche that some other companies have already started to jump into.
Finally, perhaps they can charge corporations on Twitter a fee. I think this is very fair, and should not disenfranchise current individual contributors. The beauty of this is that companies will be followed by people that are already interested in them. It is like consumer driven product marketing and placement, unlike TV where the entertainment companies try to target advertising to a demographic based on who they think will be watching the movie of the week.
I do hope Twitter is able to find that right balance between making money and keeping it's users happy. It is a terrific service that allows people to express themselves and keep up with friends, associates, and family. It allows you to show your life in motion, and to answer that constant question: "I wonder what so-and-so is doing right now".