OSF UNIX is the future. No single vendor will survive this multi vendor effort. (1994).
The object embedded desktop is the future! Apple and Microsoft bets a lot of money on this. Those who do not adapt will perish. (1996).
IA64 is the future. It is completely backed by Intel and will rule from the PC all the way to the supercomputers and mainframes. Other players will be run over so drop your own efforts and join while you can. (1998).
Thin clients are the future! Since everything will be written i Java anyway nobody will want a PC. (2000).
Desktop search is the future. Any desktop will need to implement metadata indexing this year or the users will abandon them completely. (2002)
These predictions come and go every few years and from the perspective of those who conceive them they are always completely inevitable. Only in a static world would their logic hold. But the world is complex and constantly changing so most predictions do not materialize.
The few that are proven to be correct creates new markets and leaves very little room for the original players to actually benefit. UNIX sort of won, with Windows as a new contender nobody expected, but none of the big players are still around to cash in. The IBM PC sort of won, but it is a market where IBM is irrelevant.