Meh. Call me a beer snob, but I'm not a fan of domestic mass-produced beer. I live in the Northwest.
I think the advent of microbreweries is having a trickle up affect on the mass market breweries.
The mass market breweries went through a period of mergers and acquisitions and consolidations in the 70's and 80's and with pressure from the street to perform economically they diluted the quality of their product using cheap fillers and extenders in their formulations to cut costs. Product quality did indeed suffer badly to where American style beers became an international joke.
The advent of microbreweries, beginning in the 80's, has educated an entire generation of American beer drinkers as to what a good quality beer/ale is all about and the American pallet for beer, as a result, has become more discerning. The end result is that the mass brewers have been purchasing craft breweries and producing higher quality craft products themselves.
Still and all, on the mass scale side, I do admire their ability to produce vast quantities of product of known consistency and quality, from one side of the nation to the other, year after year. This is no small thing. What I mean is that a can of Bud tastes the same in 2011 as it did in 1992 and it tastes the same in Hobokin, NJ as it does in San Diego or Anchorage.
From a production and logistics stand point and considering beer is a fermented product, that's no mean feat.