Choosing your smart phone is now a very difficult thing bcos,
new models are coming so frequently.
But a few things to keep in mind.
Utility required out of your phone.
If you will be using it more for buiness or social works would decide which model you choose.
It is better to have separate phones for the same bcos social tools may be used to steal your private business data more easily.
Also a 3-4 MP Camera is decent enough to have.
But if you want status you could go for higher end models with HD video recording which you could even use for a business purpose or two.
If money is not aproblem it is not very bad idea to change your smart phone every six months or 1 year with the latest shine in your hands and a smile on your collegues face.