Aah..the kuksa!
I read through this thread a few weeks ago, and thought I`d contribute....I`ve had the same Kuksa for the past 11 years or so, and found it to be (in addition to a few knives) a favorite piece of equipment. It doesn`t burn your lips, floats in water, is a natural product born out of craftsmanship...and is way more aesthetically pleasing than a plastic mug. I received mine as a gift from my parents, when they came to visit my wilderness hideaway (log cabin) in the Tuntsa Wilderness area in Northeastern Lapland in Finland....
The use of alcohol when first taking the kuksa into use, seemed to be one point of speculation in this thread...let me explain how it is done in Finland. Think of the Japanese tea ceremony...
It is in effect a certain type of "baptism/initiation rite" for the kuksa. Initially, you sit by the fire and measure out a dram of some treasured beverage (brandy, cognac, whisky, coffee...) with a respectful attitude for the whole procedure...

You then raise the cup to the heavens like a newborn child, and toasting to the six primary directions (NEWS+up and down), welcome the kuksa into this world as a wilderness companion. You then spill an appropriate amount to the "maahinen" (little people of the forest) asking for their blessing...and sip the nectar yourself...et voila! A lifetime friendship has begun...
Wash/rinse the kuksa only with clean water, protect it from direct sunlight and dry places...and remember to gently caress it every now and then...