Twitter plans to introduce media into the Tweet Stream. This is the worst idea in the history of Twitter.
For now, let's ignore the fail whale problem. Even though we know the server load will only increase exponentially as the stream has to distribute hundreds of images and videos along with text, let's ignore this for the greater issue at hand.
Twitter loses its fundamental purity of form by inserting media into the stream. It becomes a gimped version of Tumblr.
On Twitter, all people are equal. Everyone gets the same one hundred and forty characters to work with. Whether you want to write a funny tweet or get people to click a link, you have to write something good. You have to make your words work. Videos and Pictures integrated into the stream annihilate the need to make your words relevant.
With 100 million users, there is no way Twitter can control who is sharing what image regardless of if it is copyrighted by someone else. While this isn't entirely a bad thing, it doesn't sit right. Users go to Twitter to see a person's unique words and images. The last thing Twitter needs is to become a realtime version of 4chan.
Part of what makes Twitter so addictive is you are able to check it very quickly. Loading images and videos into the stream will increase the amount of time it takes for the stream to load. Without that quick load ability, Twitter could lose some of the potential addiction it has on mobile devices.
Moreover, this just seems to aim at destroying a huge amount of the ecosystem built around Twitter. Should Twitter choose to host images itself, image services such asTwitPic and yfrog will be decimated. Video services like Qik and Twitvid could also be thrown aside if Twitter chooses to host video. This will build a more bad blood between developers and Twitter. There is already a rift growing between them, and media has the potential to push it over the edge if Twitter shows it doesn't care for those services that have helped it grow to this point.
The worst aspect of this is that Twitter loses its fundamental equality. Nothing can compare to seeing that one tweet that makes you laugh out loud, or really think. The marvel in this is that each tweet is sort of like poetry; grand ideas crammed into as short of a form as possible. Images, video, and other media take that away.
And once that purity is lost, it can never be reclaimed.