You know, people usually expect from a thread titled 'Who We Are' to find out more about the owners of the site and forum. This:

And this:
"Eastern-rite [or, Byzantine-rite] church, also called Eastern Catholic Church, [is] any of a group of Eastern Christian churches that trace their origins to various ancient national or ethnic Christian bodies in the East but have established union (hence, Eastern-rite churches were in the past often called Uniates) or canonical communion with the Roman Apostolic See and, thus, with the Roman Catholic Church. In this union they accept the Roman Catholic faith, keep the seven sacraments, and recognize the pope of Rome as supreme earthly head of the church. They retain, however, all other characteristics – e.g., liturgy, spirituality, sacred art, and especially organization – proper to themselves." (source: "Encyclopaedia Britannica")

If you want to tell all Christians that they're welcome, then the thread should be titled 'Who Is Welcome Here' or 'All Christians Are Welcome'. Though it usually goes without saying, that all people who behave decently are welcome on an on-line forum. But perhaps you want to tell people what sort of conversations are accepted, on which topics -- about Catholic, Orthodox, and even Reformed/Protestant teachings and practices.