I've never heard that Rails would make "programmers obsolete", in fact it seems to be the opposite; if you look at the official Rails site you'll notice that the biggest tag-line is "optimized for developer happiness".

Rails makes developers happier, not unemployed. What's more, anyone can write bad code in any language, so pointing to Twitter is hardly a conclusive argument. There are lots of big Rails sites out there, including Basecamp, the original Rails application.

For a better (and longer) write up on scaling Rails, I refer you to this article.

Exactly, it's estimated that there are up to a billion asteroids in our solar system, of which an estimated 100 million are larger than 10 metres across and likely to cross Earth's orbit at some point.

It's also worthy to note that even a small asteroid (i.e. about the size of a house) is enough to destroy a city, and a larger one could wreak havoc globally, regardless of where it lands.

Also, to quote Bill Bryson, "the number of people who in the world who are actively searching for asteroids is fewer than the staff of a typical McDonalds. (It is somewhat higher now. But not much)."

And we couldn't do anything about it even if we detected an asteroid that was going to hit earth, as we don't have any rockets that could reach it in time. The Saturn V rockets were retired in the early '70s, we (as a species) now have no replacement that could even reach the moon.

You might want to have a look at Retrospectiva. It has ticketing, milestones/goals, code reviews, a wiki add-on, a blog add-on, and an Agile project management add-on. Plus you're free to develop your own add-ons. It's fully open source too...