My position is that it's a personal thing so whether you are a believer or not then you should shut up about it anyway. So guilty as charged Yorky but at least I'm consistent.
It is a personal thing - we agree on that. But I'm not as rigid in my definition of 'personal' as you are I think. I tend to oppose 'personal' with 'the State' not with 'the public', which is a very different thing. Because religion ought to be a personal matter only it follows, for me at least, that no religion should have connections to the State or tax-breaks from it. This means disestablishment and it means no religious instruction in schools.
But it doesn't follow that it should be eliminated from the public sphere. Churches, mosques, synagogues, gurdawas, druid incantation centres should all be allowed to drum up business. Their adherents are perfectly entitled to argue their case in public - by hiring Wembley Stadium as Billy Graham used to do or by standing outside Brixton tube (my station) every single day telling us we're all going to hell. So long as there's no public order issue involved I can live with this. It's a small thing.
But by the same token atheists or non-believers or rationalists or humanists (or whatever we want to call them) should be allowed their public space as well, if they want it.
I see that as a good thing. It leads to an active democracy - the cut and thrust of civilised debate. It also allows ideas into the public realm that often wouldn't normally get aired in some families. I'm thinking of a Muslim family in Whitechapel (Jewish in Stamford Hill, RC in Liverpool, baptist in Ebbw Vale etc) where the kids are browbeaten into being devout. What chance have they got to truly make religion/non-religion 'personal' if they never get access to the opposing point of view?