First off Buddy... don't worry about people that hate whining...just as many of us support your right to make your point....repeatedly if necessary....and even if you are wrong

.. (but you are getting this from a guy for whom MB had to institute a new "# of words" limit per month)
MA owns the virtual me...but not the Me me. The part where I give them money, and discuss things with my friends...that is all mine.
And we don't know what percentage would be necessary to have an impact were they to suggest that MA recieve fornication. Actually, such a strong measure would have to be an absolute last resort...and never done in the spirit with which you describe it.
But let's imagine that such an extreme situation warrented player abstinance from depositing for a period of time....the percentage necessary to get noticed (which could alone be sufficient) would probably be similiar to their profit margin. i.e. if after paying all the bills, MA gets to keep 20% for a rainy day.... 20% of players taking a break could get thier attention.
I am not saying that this would hurt MA. the goal should never be to hurt MA anyway. And MA can handle slumps...they weather one every summer, where their deposits drop off for normal reasons....so they clearly have a plan to manage down times. But, if such a drastic measure were taken... just getting a unusual report across the desk of managmetn might be enough of a victory to encourage MA to engage the players to find out where the discontent is comming from.
Yes, if you wanted to do more than get noticed...if you wanted to impact MAs bottom line significantly, you would need a larger number of people working together.... But if things ever got this bad....that players felt they needed to twist MAs arm by force of massive boycott...well, I don't even want to think about how bad things would be at that point...that would be the time to sell out.
But again, a group of playes temporarily abstaining from deposits in order to get some issue noticed, is one of the most extreme functions of a player group. There are other functions much more benign than this. Idealy speaking of course.