Not that I am hoping BR fails, but the AV industry has being known to change course? Heh.. look no further than SACD, DVD-A, and Laser Disc just to name a few? As for the "nay-sayer" who are the majority of us BR will never become mainstream untill it becomes more viable and affordable and I for one to this point am glad I've missed the boat.
Of course there will be something new at some point in the future; that is necessary for progress. This means that, eventually, something will replace Blu-Ray. But that will probably be many years in the future. In the mean time, the best picture you can get in consumer products for the U.S. market is Blu-Ray (or an old HD-DVD player). For a glimpse into the possible future, take a look at:
http://forums.audioholics.com/forums/showthread.php?t=44276
I am a bit puzzled why people are always bashing Laserdisc, as it was the best U.S. home video format from the end of 1978 until 1997, when DVD appeared on the market. It was never popular because the discs were always expensive, and the players were always expensive. There are technical reasons for this (in part, it was due to the size of the discs, as a laserdisc player must be vastly more robust than a DVD player). Be that as it may, for people with money, it was a great format for the time. The format remained the best U.S. consumer format longer than DVD did (DVD was the best format for less than 10 years). Perhaps you should instead be complaining that DVD is just a flash in the pan.
As for changing course, we can say that the industry is doing just that with TVs themselves. The old format of broadcasting will be gone in less than a year. Undoubtedly, the current HD and other digital broadcasts will not last forever, either. But that is no reason not to buy a HDTV or a tuner to receive the new broadcasts. The format (actually, formats, as there are multiple ways that they broadcast digitally now) will most likely last longer than the vast majority of TVs made today. But it would be foolish to think that they will last forever.
As an aside, I keep using the phrase, "for the U.S. consumer market" because there are better formats for picture quality. A good 35mm film is better than Blu-Ray, and, of course, 70mm film is much better than 35mm. But they are not convenient for most consumers, and are not made for consumers to use in their homes.