Thanks for pointing this out. I had posted an early response in this thread (back in April when no one was driving 2010s). I reported no problems with my 2007 and hoped for the same for my 2010. I do see a difference with my 2010. I wear polarized lenses, and I notice a drop-off in visibility -- not the speedo, but on the MID. The LCD screen (NAV) is just fine. I may look for some non-polarized lenses for driving purposes, but I still will prefer the polarized ones.
Anxious don't be concerned. I have no problem whatsoever reading my instruments with my sunglasses. They are not polarized shades however (but I had problems reading instruments in aircraft which is why I have to live without polarization). As far as the comment "hard to read without glasses" indicates the reporter needs to visit the eye doc. All instruments are clearly observed in the 2010 model. You'll love your new car.
By the way the link for the rest of you: New Toyota Prius: More posh, more power and more mpg - USATODAY.com
Unfortunately the USA Today writer did not bother to get all of the facts. Two facts he/she missed were: (1). Polarized sunglasses and LED illumination work against each other. Use non-polarized sunglasses. (2). The dashboard lights can be almost doubled in brightness by turning the brightness wheel all the way up and then pushing the wheel a step further. You will feel a click, and the dashboard lights become much brighter. There is no excuse for a high-tech USA Today writer being behind the curve.