Are some of the Civ 5 achievements bugged?

The good money is on the achievements being either bugged, have not been "activated" for earning, or something else entirely.

At any rate, they are currently un-earnable, though if the patch last week fixed them, all bets are off (and there's some evidence that it did, see comment below).

I just won my first Victory with Harald of Denmark. No achievement.

My berserkers are currently headed towards Firaxis.

Also, I won on a huge map, by taking out everyone else... apart from the ones that died to others (like poor Gandhi who spawned next to the nice and peaceful Alexander the Great). I have a lot of heavily upgraded and very experienced berserkers...

Note: I specifically sent a ski infantry to get the biathlon one, worked right fine, a few turns before winning. So the achievement functionality is just fine, it's only working... not always.

Conclusion: two years later, the game is still buggy on achievements :D