While I agree that in most cases there are winners and losers, Cameron has in this instance set himself up for a hard time from a huge part of the community. Anyone born before April 1951 will be treated differently to those born after - there is a huge number of people involved here (moi aussi ).
Personally I think that Cameron will change this closer to the implementation date as it has the potential of losing him that 'grey' vote which is so important to the Tories. As things stand just now it would cost me £2520 per annum. Note: I say 'cost' but it will not cost me anything as I won't be getting it, but I will be £2520 per annum worse off.
I would write to my MP but she has shown herself to be as useful as the proverbial chocolate teapot. Maybe I will write to that nice Alec Salmond and see if he can help