I love JetPack and use it on several self hosted blogs. But I have run into a major stumbling block.
Anytime I try to edit an existing post, clicking the Update button does nothing. This even happens sometimes when I am trying to Publish a new post that has been previously saved.
If I exit the article and edit it again, WordPress shows that there is an automatic backup that is newer than the current article.
The only work around I have found is to deactivate JetPack, update the post, and reactivate JetPack. This is happening on several of my websites.