Why did the band nightwish get rid of the lead singer tarja?

anyone know? its bugging me...although the new singer is ok, im still wondering whatever happend to Tarja...D=

for those who don't know, nightwish fired singer Tarja with an open letter.
Tarja responded with a public post from her website.
http://www.nightwish.com

they said her attitude didn't match that of the band's.
read the open letter here
http://www.nightwish.com/en/article/6

I miss her, I don't like anette olzon as much

OMG Tarja was so much better
I don't dislike Anette, but it's just not the same!!
apparently Tarja had a "different attitude". I didn't even look at the letter yet, but that's all I heard.

Ok I read it. I really don't think she really ever "wanted" to leave, but whatever. She's still awesome! Anette's all right. But I honestly think Tarja is what made Nightwish what it was! Blehhh =/
Anyway...why did Anette join a Finnish band when she's actually from Sweden? THAT'S kind of a good question right there! LOL!