it's clearly microsoft influencing the market, either in acceptable ways, like flooding the market in terms of advertising and product as well as more questionable ways like deliberately targetting some standard or protocol simply so their own proprietary standard will become the "de facto", or even by using the old carrot-and-stick technique to ensure that retailers push microsoft products only.
but if it were a level playing field, then the consumer would get the choice of any OS, because software is intangible, the cost is a licencing cost, it makes no difference to the retailer whether you get a PC with ubuntu or one with MS Windows, no difference except perhaps the cut the retailer gets from the sale.
