It's become an article of faith in mainline churches to declare that "all are welcome." Sometimes there will be a rainbow flag to seal the deal, implying that gay, lesbian, bisexual and transgender people are welcome to attend services, become members and possibly engage in leadership. Maybe. Since it all depends on attitudes and policy, and if and where these differs from actual practice. Sometimes a vague welcome to skirt a denominational policy, or to manage internal conflict. But nothing objectively welcoming LGBT people, and for a long time that's as good as it got. But it's not the 90s and that's not good enough any more.
I've disliked the formula "all are welcome" for years. The logic reads to me this way: that LGBT people are so outre, so exceptional, so horrible that everybody else has to be included before their needs are recognized. Um, thanks. In practice, some people are not welcome at any particular church, say, at the very least persons who are an immediate harm to other people should not be welcomed. (If they're welcome, their victims aren't.) Other churches can pick up the slack for that abusive husband, thank you. "All are welcome" gently merges LGBT people and the truly despicable or dangerous.
Also, welcoming assumes an attitude from one group to another, as if LGBT people haven't been in the churches all along to welcome newcomers.
The initiative Church Clarity provides defined standards for LGBT inclusion and women's leadership. Churches can self-report, but anyone can ask out loud how clear a church's policies are.
So, to the churches, liberal or not: be true to yourself, but be honest with those who are coming to you. (This is especially the case with churches with a progressive aesthetic but conservative morality, particularly among the non-denominational Evangelicals.)
Don't wink and nod and think that makes progress. State your policies clearly, and stand by them.