[link text][number] format don't work properly if they follow a tag using the new
[tag:tagName] format. Here's the result of
[tag:python] [gold badge page]:
Putting the tag inside the link is worse. Here's the result of
[[meta-tag:bug] some text], where
The part of the link outside the tag just disappears silently.
To be more precise, the entire link to
 disappears. The markup that is produced contains (invalid) nested anchor tags, as shown here from Firefox's "View Source":
<a href="http://google.com" rel="nofollow"><a href="/questions/tagged/bug" class="post-tag required-tag" title="show questions tagged 'bug'" rel="tag">bug</a> some text</a>
So the tag is still a link, but it is a link to the tag page, which is the behavior it would have if the link to
 didn't exist at all. The user's desired behavior in this case is... ambiguous, to be charitable.
I briefly included markup from Firebug here, but it turned out to be irrelevant. It has now been removed to improve readability. See the revision history if you're interested.