Two reasons not to be a liberal Christian:
(1) Archbishop Rowan Williams, head of the Anglican Church, 'explores' the inevitability of Sharia law in Britain. Somehow, Williams missed the fact that Anglicans in Nigeria are currently being persecuted under Sharia law, or maybe Williams knew but just didn't care. One hopes it's the former, but I can't help but think, with the behaviour of certain Anglican leaders in mind, that it could just be the former.
(2) Catholics in the Netherlands have decided to start calling Lent, 'Christian Ramadan'. Yea, that makes as much sense, both practically and theologically, as Dutch Bishop Tiny Mueskens wanting to call God 'Allah', to foster better relations between Christians and Mohammedeans. I feel for the 400,000 Dutch Catholics who actually still attend Mass on a weekly basis, but who must becoming inured to the outright stupidity of their ecclesial leaders.
I guess the positive side of the decay of liberal Christianity is it that it will eventually lead to Christian reunification. On the negative side... well, there's just too much to mention.