Automatically get updates

Is there anyway to register interest in a company and afterwards get a call back with any changes?

It’s a popular request:

… and the answer seems to be:
a) No but there is a partly manual process which accomplishes this (the “Follow” service).
b) CH have been mentioning a “streaming API” which may cover this among other things but this has been trailed with no timescale for more than a year now…