A feature that I found confusing was the "Mark this version" button. I wasn't entirely sure why I was marking it or what I was marking it for. Perhaps different terminology would make this feature clearer; maybe something like Set as Important. Also, the purple dots beside each version could be made clearer using a more descriptive alt or title text or better yet, include a rollover that details what the dots mean (they indicate the amount of change in the document from one version to the next).
I'm also intrigued as to why you can only Export as Text. Why not RTF or Word or PDF? Export as Text leaves me with no formatting. Using the email feature did send me the writeboard in its HTML format but there was no indication as to what the email was about. The writeboard name was the subject line and the writeboard contents was the email. In fact, this could become a great way to set up e-mail newsletters (or spam but let's hope there's spam control in there).
This is a pre-release web application and the feature set is likely to change before the official launch. I'd be interested to hear how others plan to use Writeboard?99热这里只有精品国产，免费99精品国产自在现线，99国产这里有精品视频