Earlier quoted context omitted.
why would it be better than say fingerprints ? Is it the fact that fingerprints, or retinal scan cannot be cheaply integrated into a mobile phone... while this can be?
No, it's because an evil person will cut off your finger in order to gain access. He can't rip out your beating heart and all the sanguine system so this is a much better biometric from a personal safety viewpoint.
for online or remote authentication all bio-metric identifiers are as bad as each other. you can simply "play back" a stolen signiture. if a human is present to observe then maybe it's a little harder. nevertheless, your signiture is effectively worthless if it does get stolen - and when it is you cannot change it.
I'm strongly of the opinion that bio-metric id is a disastrous concept. As well as the issue of having signitures stolen, such systems will evitably result in further erosion of privacy. Plus of course, with possibly the exception of your DNA, you change over time, meaning that, I beleive, such systems can never be that reliable.