From Kunstpedia blog in the Netherlands:
Rembrandt discovered in depot of museum
* By: Kunstpedia Administrator
In preparation of an exhibition which would be held in Japan the painting, supposedly painted by a pupil of Rembrandt van Rijn, was ready to be restored. The Rembrandt specialist Ernst van de Wetering however discovered and conformed that without doubt the painting is by the master himself.
Painted in 1659 it shows a man and woman in front of a fireplace. Rembrandt painted the scene over a still-life, which barely shows through the thin layer of paint in certain areas.
The work of art shows, amongst others, resemblances with Rembrandts etching “Peter and John Healing the Cripple” from 1659. Van de Wetering furthermore comments that the position of the two figures, the manner in which they are placed in the scene and the feeling for detail all indicate that the painting is by Rembrandt van Rijn.
As from Friday 8 October 2010, the new discovery will be on display in Museum Boijmans Van Beuningen for a month, before the masterpiece will be restored.
See also here.