There is a new journal of the European Mathematical Society that seems perfect for these articles: EMS Surveys in Mathematical Sciences. The description at the link reads:
The EMS Surveys in Mathematical Sciences is dedicated to publishing authoritative surveys and high-level expositions in all areas of mathematical sciences. It is a peer-reviewed periodical which communicates advances of mathematical knowledge to give rise to greater progress and cross-fertilization of ideas. Surveys should be written in a style accessible to a broad audience, and might include ideas on conceivable applications or conceptual problems posed by the contents of the survey.
I am actually quite excited about this, as there are some notes I've been sitting on trying to find an appropriate place for them. This may be the solution.
