I've been a fan of the press for its simplicity, taste and price point. When I got my order in from sweet marias (took over 7 weeks, woo!) I got a thermometer, so I was ready to test my actual brew temperature.
I'd let my electric kettle turn itself off, and pour boiling water at 212F, let temperatures equalise with the lid on to about 190F, when it starts to lose heat at a steady rate as opposed to a sudden decrease due to the equalisation of glass/water temperatures.
Then I'd pour the water into my mug to get it nice and warm (as well as to clean it, and the filter assembly). I'd pour in the grounds, splash in a bit of water, swirl to get rid of bloom and add in the rest of the water - measured at 203F, cover it with the filter, let it brew and press.
After that I dump the hot water in the mug and pour my 190F coffee, which is nice and piping hot. Turns out I get supposed optimum brewing temp by boiling a bit more water and preheating my press, and did so without a themometer as I had the ritual going for a while beforehand!
I think just pouring the boiling (or just boiled) water on the grounds in a cold press is a bad idea seeing as theres two bad points.
1 - The coffee will be scorched by the initially too hot water
2 - Then the coffee will be brewed by water below the optimum temperature as the glass cools the water.