This is Warhammer. It must be brutal and unforgiving I'm glad to see mature audience =) Maybe developers will see that and note it
M Ratings aren't like R Ratings. It's been proven time and time again that they don't really influence sales in a negative way.
Even if the audience polls right now as "mature", this will probably change after release. The Warhammer 40k lore is very juvenile in its nature (which isn't a bad thing in itself), so the MMO will also attract a younger audience.
I'd say for the Time being we are a Mature audience, but as stated before, the age will vary come release day.
RvR was a good idea but a game needs more content... I remember a 10 hours fight and when we was ending the game the server started to rebot