Why use something like 10 tweets where a blog post lets you have as many words as necessary. You can still be concise but 140 char is too short, it's just for people that have uninteresting things to say and Snowden is certainly not one of them (unless he starts to comment about the weather in Russia).
While a blog would be much better quality, quality journalism doesn't sell nearly as well as highly-polarised, bite-sized clips.
While a blog is a better authoring medium, it's still shit for discussion, and loses some of the media impact benefits that Snowden probably intends to leverage here.
If you don't want to wait until it's ready, I recommend tweecha - or install Google Chrome from the Play Store, that should make Twitter automatically use the Chrome webview instead.
How about a screenshot with a link to the text version for those sufficiently motivated? I know most people don't care for accessibility, but sheesh, that simple courtesy would mean the world to those who use screenreaders.