I'm raising this debate because I've been thinking of Steam's hold on the PC digital distribution market. Although Steam doesn't actually completely control the entire specific market, no other service rivals Steam's market share, with competing services such as Direct2Drive and Gamersgate (as well as many others) only holding a smaller portion of the market. Steam effectively fits the definition of a monopoly.
Is Steam's monopoly a good, neutral or bad thing for the consumer? Arguments for being good would include providing ease of use for users with only a single service, neutral being that the developer or publisher happens to set the price of Steam titles, not Valve (therefore price wouldn't be debatable in this issue). Arguments for being bad would be consumers investing completely into only one service, one which may go down in time or one that is subject to much change from only one party. I'm sure we can think of more, can we?
This debate doesn't have to be just about Steam, but about monopolies in the market in general. Can a monopoly ever be of benefit to a consumer, even though it reduces much choice for such consumer?
I should specify that we should be debating monopolies in the private sector, not public. Apologies for not mentioning it earlier.