Also, while scaling may be a non-trivial challenge, going to over ~100,000 page views a day (95% are between 8am - 6pm) was pretty easy, and very little fuss.
To me real scaling is where you're having to run a cluster since a single server is inadequate to handle the traffic, where you're having to implement or leverage various application caching schemes, etc...
But remember that a lot of people who start with Rails are not sysadmins, and may have absolutely no idea how to scale anything. I'd bet they'd probably hit the same scaling trouble if they used anything.
If you listen to folks that have had to scale out to meet demand, you hear the same thing repeated: once you get beyond a certain number of connections, things like choice of language level out and you have other things to worry about. Default installs of WordPress don't scale either, because of database load. That doesn't necessarily mean that WordPress can't scale.
Like anything else, Rails can scale, but often times those deploying it just don't know how. I know I sure didn't when I started out. And every web project I've been on has had different scaling needs. Rails has, in my experience, been easier to scale out than the ASP or PHP apps I used to maintain.
This fascination with scaling is hazardous to the health of both the startup and engineering communities.
To recommend against rails based on the assumption that it'll scale badly in cases where it has to handle more than 100k views per day isn't really helpful.
Once you reach these values, chances are, you'll have team, budget and need for a custom solution anyways.
Now, I'm no rails developer and I never got to really like the framework. So if you ask me, I would find other issues that prevent me myself from using rails (many personal soft-facts - a matter of preference). The (supposed) inability to scale beyond 100k views/day isn't one I'd consider first
Can you explain how Rails doesn't handle this? Because all of my (admittedly limited) experience says it handles it just fine.