Following on from Google Analytics recent update that includes the ability to add notations to track significant and key events such as new campaigns, new content or site changes. The team at WordPress.com appears to have followed this lead and has also rolled out a new feature which automatically adds annotations when a new item is posted.
This feature is only visible on the current period of time shown in the stats window and only when viewing views per day, not week or monthly data traffic. While it is likely this feature will be expanded and improved it is a great start and makes it easy to start to understand how recent posts influence your website traffic.
It would be great if this could be further improved to allow the ability to see how particular post tags or categories attract visitors to your blog, as a following update to the stats reporting. Being able to see how popular particular post tags or categories in relation to traffic is a real benefit for bloggers using the free hosted version of WordPress.