It looks like the manufacturers rediscovered that AA batteries are much better at powering high intensity rear lights than their AAA poor cousins. Considering that a large minority of people are not getting on the USB-rechargeable bandwagon for whatever reasons, I noticed couple of new lights for this season. They are Blackburn Local 20 Rear Light & Serfas 9-Led Cross Pattern Bicycle Taillight - TL-STP:
Amazon.com : Blackburn Local 20 Rear Light : Sports & Outdoors
Are they any good for daytime riding?