Nope, but it doesn't surprise me. I found bitbucket's markdown so limiting that I gave up on it. I suspect they'd rather have their users on Confluence instead.
The markup Atlassian uses in Jira isn't Markdown at all. It has a few general similarities, like the use of asterisks for bold, but otherwise it's so different as to essentially be its own thing. (For instance, it uses [text|http://example.com/] for links, which isn't even remotely like Markdown.)
But if one of your main selling points is integration, you'd better standardize to one, especially if (as an other commenter pointed out) the one in bitbucket is subpar.
No argument there - but no surprise either that upgrading bitbucket's markup might be something lower down on the priority list for the Atlassian engineering team either. :)
