Personally, I'd say it's a very courageous thing to bet against a community with that sort of track record.
For anyone who concludes that since Linux doesn't have the desktop today it never will, I can only shake my head and wonder.
Computing has only been a 'mass market' thing for what, at most ~5 years? It's a very immature market. Anyone who thinks the way it is now bears any resemblance to the way it will look as the market starts to mature sure doesn't have much of a sense of history, I think.