I was hesitant to upgrade from kindle keyboard too, I loved it, loved the buttons and was also worried about having to avoid the touchscreen, but honestly I love the new paper white even more.
The main reason I got it was the light which is amazing, but the best thing about it is for me a surprise - it feels so much nicer to hold and use. It's so light, slim and small, much easier to leverage than the old kindle. It's actually a lot more comfortable to use than the old kindle which I really didn't expect.
I used to hold the old kindle in really weird angles to have constant access to the buttons but now I have this I don't have that problem anymore, I never even knew it was a problem.
Anyone curious about the upgrade but nervous like I was, give it a go, I regret nothing!