I think it was a bit of a knee-jerk reaction, but investors do realize that the end won't be tomorrow for GPS makers, but it will certainly be in the next few years as new android sets come out.
I respectfully disagree. It is not a knee jerk reaction. The writing is on the wall for many single use 'gadgets': gps, point & shoot cameras, calculators, etc. It is not google per ce, but powerful pocket computers (iPhone, Android, etc.) that is driving the change. There will always be a need for niche single use gadgets, but for the mass market the multi-purpose pocket computer will dominate.
It is deja vu all over again.
It is a knee-jerk reaction because Garmin presumably is going to react and may even get into the Android game themselves. It's too soon to write them off.