No no no ladythumb that is not right! AIBU to just think congrats and then get on with my life - why be spiteful about it just because its the internet and a famouse type? It's not really unusual at all.
I am thrilled for them - and I don't care if that's very sad! I have 3 DS and then a lovely DD (sorry, the DS are lovely too!) and I totally understand how excited they must be. Plus it's just lovely having another baby!
Don't particularly care about what they call her - each to their own!