After speaking with other owners, one which spent considerable time talking to the mechanic at the Smart dealership, there seems to be two issues that are known, one of them rather major.
1. The shifter has a defect that will, one day, fail to shift your car into gear. If you shift into reverse, then put it into D, the shifter may fail. If it starts working again you need to contact Smart FAST before it fails completely and you're stuck somewhere waiting for a flatbed.
2. Your engine light will come on eventually. Don't let anyone just reset it, they just need to replace a simple $40.00 part. I have forgotten what the error code is but it has to do with the injection system/computer.
3. If you have the sunroof with the screen, it works like blinds. If you roll it back from a closed position to half open then close it again, it may, or will eventually, do what blinds do and stop working properly. The solution is to "finish what you start"... don't close after opening half way.
4. The radio will turn on when the car starts every time. Damned annoying to me but not a deal-breaker.
Okay, that's four things, two rather minor.
The maintenance guy at Smart says those are the only issues they are aware of country-wide.