I might have found a of bug, can anyone verify.
When inserting a link to another page or blog entry into an entry’s Excerpt, the link doesn’t get built when displayed on the front end. So it just appears as
<a href="page:[about]" title="About">About</a>
<a href="entry:[yet-another-blog-post]" title="Yet another blog post">Yet another blog post</a>
This is only the case in the Excerpt not in the main content of the entry.