Lighting turning up on readers would not be any incentive for me to rush out and replace my T1. But if, for other reasons, I had to replace the reader I would consider it but it would not be a biggie in the decision for me.
I have been reading ebooks for many years on PDAs and more recently smartphones, and they, of course, had lighting. My collection of books is predominantly epub and when I eventually started looking around for a reader the T1 seemed to be the one that would meet my needs at the time and avoided the proprietary ties most others have. Then, purely by chance, I was given
a T1 so the choice was made for me.
I had wondered if I would miss the lighting, but I have not at all. Everywhere I read where ambient light levels may be low (bed, planes, boats, etc) there is always a reading light available. While I understand the differences between LCD, etc and E Ink with respect to reading comfort, what I can say from use of PDAs and phones is that it was very important for easy reading in different ambient light levels to be able to adjust the device's light level, and if in the dark, or very low ambient, then to be able to set up the background in a neutral colour (such as sand) for ease of reading. I wonder how well the early lighted readers will handle such circumstances, and is something I would want to assure myself before buying one.
So I have not even considered getting a clip on light as I could not see any advantage for my usage, and meaning just one more thing to cart around, keep fed with batteries, etc.
I have also used audio books for many years (PDAs and then smartphones), and while the T1 does audio I don't use it as a phone is far more convenient, as well as doing the job much, much better. I suspect with the big uptake of smartphones, audio on readers is becoming, for many, redundant, and may be part of the background to the decision to dump it from the T2.