Here is a list of the common questions (and answers) we've been seeing:
How do I get my latest post to be at the top of my blog?
By default, when you publish a post, WordPress will the post as the top post on your blog's front page. If you've set other posts to Sticky, those will take priority at the top of the page. Many users had been using Sticky for every single new post. This is not the correct use of the option. You should only be using Sticky for one or two posts that you ALWAYS want to be at the top of the blog or at least until you edit them again and remove Sticky. Some blogs will never use the Sticky option. If you need to go back and edit posts to remove the Sticky option, see http://support.wordpress.com/posts/7/
Where is the View Site link?
You can click on your blog title next to the WordPress logo in the upper left corner. (We have added a little arrow with the words View Site to help with the transition.)
Why don't my images/docs/pdfs have links?
Make sure to click the File URL or Post URL button before you click the Insert into Post button. Once you've done this, your choice will be remembered for next time. See this screenshot: http://skitch.com/mtdewvirus/7587/mdvtester-add-new-post-wordpress
Why can't I insert different image sizes?
Make sure you've set the sizes for thumbnail, medium, and large at Settings->Media.
Where is the Discussion (or other) module on the Add New Post (or other) screen?
In the upper left, click Screen Options to be sure you haven't hidden the module. If the Screen Option is checked off and all you see is a gray bar with the name of the module, click on the bar to Open it. You can configure many things on the Dashboard screens. Check out http://support.wordpress.com/screen-configuration/ for an example walkthrough.
Where are threaded comments?
The settings are hidden until themes can be updated to support threading and paging.