At the start of February we had 10,000 bitcoin nodes. Now we have 8,500 and
still falling:

   http://getaddr.bitnodes.io/dashboard/chart/?days=60

I know all the reasons why people *might* stop running a node (uses too
much disk space, bandwidth, lost interest etc). But does anyone have any
idea how we might get more insight into what's really going on? It'd be
convenient if the subVer contained the operating system, as then we could
tell if the bleed was mostly from desktops/laptops (Windows/Mac), which
would be expected, or from virtual servers (Linux), which would be more
concerning.

When you set up a Tor node, you can add your email address to the config
file and the Tor project sends you emails from time to time about things
you should know about. If we did the same, we could have a little exit
survey: if your node disappears for long enough, we could email the
operator and ask why they stopped.