Next? No, I think there are dozens of plant and animal species on the brink of extinction. Humans most blatently will become extinct one day, but I think it's too far off for anyone to actually worry about. If a comet is headed straight towards Earth, hopefully we'll devise technology enough to protect us.
But, if you're looking for human extinction, I think you need to visit this site:
The Voluntary Human Extinction Movement. Credit to Anna (One Two, Middlesboogie) for finding and sharing this.