Pros: Twitter is extremely popular! It's really easy to use and once you find interesting people/topics to find- you get exposed to a wide variety of opinions, fact, cat poems and rich people telling you how great it is to be rich. You get a little bit of everything. You can get very up to the minute information (like the presidential debates) and news. My friends will use it to promote their business and their social lives. It can be great for an educator looking for inspiration and ideas.
Cons: Your extremely limited what you can tweet.. 140 characters max. This is the entire design of the software to limit characters, but with no photos, video or even a descriptive paragraph, it's hard to have much actual content. It's also hard for me to trust twitter as a source of news and legitimate content, when there are more posts about what people ate, where the coolest new nightclubs are, or Kim Kardashian's new purse. In addition, The posts I really want to read are easily buried by the sheer amount of posts being generated- so unless it becomes a serious part of your life- it's hard to stay up-to-date.
I'm writing about twitter (again) because it's part of my grad school course (again). My thoughts on Twitter really haven't changed in the past year. I think like any tool it has some great uses. However, I am a bit of a luddite when it comes to digital social media. That's another rant for another day!