It has no benefits currently but later when heavier apps are made,it will be very useful.I think Qualcomm makes 64bit chips soon,but maybe it never does that because it knows what is best.,but anyway I don't think it's gimmick, even if it's gimmick it is a new feature and it's much better than fooling people with cheating in benchmarks and numbers that samsung shamelessly did it again.
Price iPhone 5s should be no more than $ 400
As well as 4-inch screen
Thick bezels. If it were thin bezels could fit into the same body 4.5 inch screen, but apple do not care at all, and the fans continue to eyeball on an uncomfortable 4 inch and assume that it's cool
Distorting the resolution (resolution adjustment to video)
Small sensor (twice less than xperia z1 and three lumia 1020)
No aspherical lens lens
No optical stabilization
No support for 4K video zoom during movie
No 12 MP to zoom during shooting
No 4gb RAM for 64 bit processor
It is true that the current generation of iphone doesn't take advantage of the 64 bit soc. But i do think that it is a good thing for the future. The transition from 32 bit to 64 bit is going faster and begins sooner this way. (From a Nexus user).