Ok, let's try again. The problem isn't the solder as such, the problem that Nvidia is having is that in a notebook, the GPU is heated up and cooled down very frequently, especially as the fans in a notebook are generally set to produce as little noise as possible. This is why some notebook manufacturers have issued BIOS updates, but if you install these BIOS updates, you'll get more fan noise, as the fan will be running at lower temperatures and most likely run at full speed at lower temperatures than before.
This cycle of heating and cooling, with a huge temperature difference within a reasonably short time span is what has caused the solder to crack which in turn has caused the GPU cores to lose connection with the chip packaging. We're not talking the whole GPU losing connection with the graphics card PCB or motherboard PCB here, but rather the tiny little thing ontop of the chip packaging and that's where the problem is.
The same problem could occur on a desktop card, but as desktop cards have a bigger cooler and generally doesn't heat up and cool down as quickly, nor as often as a notebook GPU, it's highly unlikely that anyone will encounter their graphics card failing because of this problem. Yes, it could happen if you turn on and off your system and run some intense 3D application and you repeat this every 10-15min, but I don't know anyone that use their PC in this way.
Nvidia still mucked up and there are potentially a lot of notebooks that could fail because of this, but the question is how many and how soon...