LGBT-issues aside, he seems like a decent guy on the surface... hopefully we'll at least see some incremental changes in the church.
(no, a thousand+ year-old organization probably isn't going to turn on a dime and suddenly embrace gay marriage, women priests, etc, but maybe he'll throw the abusers to the wolves)
After reading up on his history, I would say there is little to no chance there will be a change in the official church stance on homosexuality. I am hopeful he will cleanse the church of abusers, due to the name he chose.
Saint Francis has been called the man who lived his life the closest to the way Jesus wants us to live than any man since, well, since Jesus Himself. I cannot attest to the truth of that, but what I have read said many scholars agree, so it is good enough for me.
If he has the political will to do it, he can change the world for the better. Start by cleaning house at home, then move on to spreading the great wealth of the Church into building infrastructure for the poorest people of the world.
I am very optimistic this will be a great Pope. For full disclosure, I have no dog in the race. I am a Messianic Jew so I do not follow the Pope's rulings at all. He is very Jew friendly, so that is a big plus for me. I just recognize the power the Pope can command if he has the will to wield it.