well there are too many points have be speculated out of my OP. never mind, not worth to reply.
as to your point, and as mentioned a bit by alanpotpot, maybe plus a another point of broader range of options, how a company performs in market tells.
eg, it is saying SONY is going to terminate its full frame line because of no profit, which may link to full frame lens product lines. anyway Pentax is not able to introduce its full frame any soon, if there is one.
But you'll see how profit affects a company strategy, then the end users. not mention less choice, less stock, less dealer, less service and so on. ok, not image quality related.
as to sayings like "stick to what you have", what's the purpose to make it interchangeable? and accessories? what if one link gone in your system, change whole system? stick to it with pain?
any way, one post or one question raised does not mean to be "so important", comparing to other threads here.
Frankly, why is it so important to the TS that the market share of the particular brand that important. :dunno:
So if market share is so important than we should just buy Toyota not Kia, buy Intel not AMD, Support Microsoft not Mac OS blah blah blah etc....If that happens, I felt like i have no choices in life.