I agree, it would be a big mistake for Sony to abandon CRT this early in the game, especially in the US. But if they do, there will always be a Mfg. willing to fill the gap and satisfy the market, providing the profit margins are present. Right now, the under 40" Tubes are just too good a deal for the average buyer to make a switch to Flat Panel tech that cost many times the current Tube price.
Weight & screen size are the two main drawbacks of Tubes. But for most people, these drawbacks are really only applicable if you want a larger screen than 34". Proper sitting distances for a 42" or 50" Plasma will limit screen size for many people, and the Tubes will continue to fill this gap.