I think bluray will survive. I don't think streaming will dominate, some people will want to outright own the movies, and others will have bandwidth issues with their ISP's. I don't forsee a need to upgrade from the bluray format because of its quality. To beat bluray people wouldn't need really big tv's in their homes. I think bluray might be the last optical/hard copy format. Just because they're won't be an overriding need to replace it. One thing that might work against bluray is backwards compatibility. People might be more willing to buy new titles, then go back and repurchase old ones. Movie companies make a killing off the repurchasing of old catalogs. I think that aspect might be reduced in this generation.
As for people who cite the price as a reason not to upgrade, they must of been the people who didn't buy a dvd player in the first few years. When DVD came out the players were pricey as well as the movies. It took a few years for the prices to come below 200 for a player and few more for the now cheap 50 dollar walmart players. Give bluray that much time and prices will be cheap too.