What it amounts to is operators based in the EU and operating "N" reg aircraft and relying on EU resident pilots holding only FAA licences to fly those aircraft. So, we are not taking about dual qualified pilots.
Actually, need to be explicit here - I am 'dual qualified' in that I have both a JAA PPL and an FAA PPL - but I am not dual qualified in the sense that I only have an FAA IR, not a JAA IR.
I believe the number of pilots who have an FAA IR but not a JAA IR is somewhere over 10,000 in Europe.
I know many of the 10,000 are not commercial, but all will be badly affected - me included. Like many others, I am 'lobbying' as best I can i.e. I write and e-mail frequently to MEPs, MPs etc. - although rarely get a response, and I have no contacts other than looking at the 'contact your MP/MEP' sites.
The upshot will be without an IR, no European touring, so no point in me having a plane.. so like thousands of others in the same position, I will give up flying - in the end it becomes just too much effort and pain trying to dance around the ever-increasing EASA stupidity.
So, amongst non-commercial operators - it will directly affect thousands (plus the many companies and jobs that depend upon the money we currently spend).