Linux is like electric vehicles...
Better for the microprocessor environment - YES

Lots of EDA tools available - YES (mostly little ones?)
Many happy users - YES
Does it have the software you are after - YES, sorta, well maybe. try this instead.
Widely adopted - NO
I work with a lot of exclusive Linux users.. (does PC Linux count?) I have to say, they have just as much trouble as windows users with bugs and so on if you ask me. I'm not sold on it yet at all. Alas, a great deal of "high end" EDA tools just don't support linux plain and simple.