Several teams have reported signs of an impending collapse: unusual noises (creaking, cracking, etc.), vibrations coming from the wall, and the sound of water flowing without any visible water in the Kohlmann/Clair de Lune area (extreme right hand side) of the south face of the Aiguille du Midi.
A 12-metre sized block fell down a few weeks ago. Probably best to avoid in this hot weather!