Face Unlock doesn't work very well, is less secure and much more difficult. This is hardly a "cute trick". We are going to see the rapid expansion of fingerprints in place of passwords and it is going to be pretty neat.
The problem with fingerprints is you can only change your password 10 times and faking them at readers has been easy since at least 2001(Including the ones doing heat detection and ridge depth checking).
I sincerely hope not since, as a recent HN submission pointed out, you [EDIT] possibly [/EDIT] lose all 5th amendment protections in the US when your device is no longer protected by "something you know"
Good question, not a clue but anecdotally I have never seen a finger-print scanner enabled computer that didn't use it as part of a two-factor auth as well as password in a corporate environment.
The cynical part of me thinks that the proliferation of mobile devices + the close proximity of these new devices to danger (danger being people who would quite like you to give them access at every opportunity it seems. e.g. employees of an increasingly privacy-hostile government, such as the police) in the hands of users who don't know the implications is the biggest change/problem.
