Being in the UK I did not have the luxury of choice of the Kindle Touch. It was either the Sony, Kindle 4 or Kobo Touch. I personally am not a fan of the Kobo Readers and so it came to a straight shootout between the K4 and the Sony. For me, there was only one winner and that was the Sony. I cant stress enough how useful the touch screen is despite it not being a "neccesity". The ability to swipe for a page turn is invaluable to me, especially in the days of smart phones when your fingers are instantly drawn to prod at a screen!
Whilst I do like the Kindle way of doing things in terms of never having to link to a computer, I do not feel particularly restricted by the Sony not being able to download straight to device. I know this can be done through the browser but with the Sony Store not yet open in the UK it is a bit round the houses! I quite like having to use the PC and will continue to do so even when Sony do pull their fingers out and get the store opened up!
As previously stated both readers have a place in the market and I think it does often come down to personal preference. Just fancied putting in my two pennies worth
Mike