Those who say smart meters are the devil aren't educated in physics or engineering and don't have a clue what RF (radio frequency) is.
They hear radiation in RF and think X-rays. But light is radiation. Radio waves are radiation. Only short ionizing wavelengths (like X-rays) cause cellular damage. Once the waves get longer (everything below ultraviolet light) they simply don't have the physical ability to damage cells on a molecular level.
We're surrounded with RF radiation: TV, radio, cellphones, wireless Internet, baby monitors, garage door openers.
Can it do harm? Sure, if it is highly concentrated (like your microwave) it can heat cells up and damage them that way. But despite the bogus Internet Academy of Environmental Medicine statement, there is absolutely no peer-reviewed study that has found any other harm.
If people are worried about smart meters, first they need to get rid of their cellphone. That is far, far stronger than a smart meter. Then get rid of wireless Internet (and don't visit coffeehouses with wireless) and the baby monitor.
Then, and only then, would it make sense to be concerned about the relatively weak and short bursts of smart meters.