I was under the understanding that there would be an interchange at Drumcondra. Of course, this is Ireland, so (if it ever gets built), the Metro station exit will probably be down the road and across the street from the Irish Rail station...
Sadly they turned down the sensible proposal of a new station a little further west, under the tennis courts at Whitworth Road with platforms for both the Sligo line and the Midland line, serving Glasnevin and Phibsborough.
http://www.dublin15cc.com/documents/...submission.pdf
James