My family and I just joined our local United Church of Christ congregation (Tehachapi Community Congregational Church). We are very progressive - influenced by the Sea of Faith movement (which is technically nontheistic - I was introduced to this when we were Episcopalians at a very progressive parish), Christian Universalism aka Universal Reconciliation and other progressive Christian thought. This church has been very open and welcoming to us!

Of course, like any other mainline denomination, not every UCC is progressive.

Dave