Looks like nicotine actually does promote insulin resistance.
Long-term Use of Nicotine Gum Is Associated With Hyperinsulinemia and Insulin Resistance
Weight gain and insulin resistance during nicotine replacement therapy - Assali - 2009 - Clinical Cardiology - Wiley Online Library
And perhaps even more alarming studies...
Nicotine Induces Proinflammatory Responses in Macrophages and the Aorta Leading to Acceleration of Atherosclerosis in Low-Density Lipoprotein Receptor
Nicotine stimulates angiogenesis and promotes tumor growth and atherosclerosis - Nature Medicine
What's everyones take on that?