Nope. The GPUs get plenty hot. The difference is that with Litecoin, your CPU gets hot too! I have not dug into the technical details, but at a glance it looks as if Litecoin motivated research that fairly successfully overcame the GPU-unfriendliness of Scrypt. If anyone here can confirm or deny this, I'd love to hear it.
The CPU doesn't get that hot. On a machine with an Athlon II 240e cgminer uses ~18% CPU vs the GPU that sits at 99% load. scrypt is indeed viable on GPUs, but it depends onto the available memory bandwidth which presumably lessens the impact of FPGA/ASIC if people start to push those as LTC mining solutions.
