There's white smoke on St. Peter's Square (at 18:08 local time). Given the time it's probably been the fourth round of voting that yielded a positive result. You can watch the vatican media livestream here with english commentary and here without any commentary.

Thought I'd post this as a text post to keep it updated with relevant information (e.g. who it is) over the next hour or so.

The swiss guard has arrived on the square shortly after 18:30. If the previous two conclaves are anything to go by it'll be another 30 minutes or so until Cardinal Mamberti will step onto the balcony to announce the new pope's name.

Update 19:13: Mamberti has entered the balcony and is making his announcement (rewatch here):

Annuntio vobis gaudium magnum; habemus Papam:

Eminentissimum ac reverendissimum dominum, dominum Robertum Franciscum, Sanctæ Romanæ Ecclesiæ Cardinalem Prevost, qui sibi nomen imposui Leonem XIV.

Pope Leo XIV, formerly Cardinal Robert Francis Prevost, is a US American by birth, but moved to Peru later on and became bishop there, making him the second pope from America and first ever US American to hold the title. He's generally viewed as a compromise candidate between progressives and conservatives within the catholic church as far as I know. He was created (as a cardinal) by pope francis and was responsible for personell management under him.

Update 19:23: Pope Leo XIV has entered the balcony and is making his first public statement (rewatch original here or with english subtitles here).

Update 19:40: After speaking for more than 10 minutes (a lot longer than his predrcessors during their first appearance) he's now issued the traditional blessing 'urbi et orbi' and has left the balcony.

Current news:

Catholic News Service: Pope revises catechism to say death penalty is 'inadmissible'

British Broadcasting Corporation: Pope Francis declares death penalty inadmissible in all cases

Australian Broadcasting Corporation: Pope Francis changes teachings to oppose death penalty in all cases

New York Times: Pope Declares Death Penalty Inadmissible in All Cases

The lead-up:

CNN (3 years ago): Death penalty showdown: The Pope vs. the Supreme Court

America: The Jesuit Review of Faith & Culture
(1 year ago): Pope Francis: The death penalty is contrary to the Gospel

And... a contrary opinion from The Catholic World Report one year ago: Why the Church Cannot Reverse Past Teaching on Capital Punishment