The discussion continues about whether this class of insecticides have an effect on honeybee decline. The summary provided at http://www.nytimes.com/2012/03/30/science/neocotinoid-pesticides-play-a-role-in-bees-decline-2-studies-find.html?_r=3&partner=rss&emc=rss&pagewanted=print suggest that exposure makes honeybees vulnerable to disease. As you might expect, there is opposing opinion from others, notably the scientists from Bayer CropScience, the largest producer of neonicotinoids.
Stay tuned for more....
Update: May 23, 2012
Discussion has begun regarding the studies noted in the above links. Some scientists believe the design of the studies was flawed making the inference that neonicotinoids are damaging to honeybees uncertain. As I understand the questions and objections to these studies, those who area objecting are not saying that neonicotinoids may not be damaging to honeybees - they just don't believe that these particular studies do not support the contention that they are killing bees or causing them harm. Stay tuned for more as this story unfolds.