With a hat-tip to Lélé, who pointed this out to me, below is probably the best video of a progressive failure event that has appeared to date.  It has been posted on the rts.ch website.  This is a landslide that occurred at Riddes in Southwest Switzerland on Friday.  It had volume of about 60,000 cubic metres.  I have tried to embed it, but WordPress does funny things (life was so much easier on Blogger sometimes!), so if it doesn’t work take a look here:

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The block was presumably creeping, generating the collapses at the margins.  The event (rockfall) rate noticeably increases before final failure.

It appears to me that there is still a great deal of material to leave this slope.