So I had my first negative experience on scheduling tweets. First off, being able to schedule tweets is a great feature, similar to how scheduling blog posts. But I do caution how far you may want to schedule those tweets out.
I ran into a situation recently where we were promoting something over the course of a couple of weeks, so it was easy to schedule some future tweets with some different teaser text a couple of weeks out. This was not related to an announcement or anything, just one of those fun things/offers you like to share. We were not aware of this, but there was backfire in the community around the topic after those tweets were originally scheduled and even though it did not affect the link itself, it definitely affected how you worded yourself when talking about it. Not knowing, one of our lovely scheduled tweets hits the web the following week and did not go over well.
Lessons learned: 1. even though your tweets are scheduled, peep you head in and check in on them, 2. try and not schedule tweets out further than a week, especially if it is business/industry related at all, you never know what can happen