Fix typo and broaden efficiency framing

- Fix "now now" -> "now" typo
- Reword efficiency intro to cover both large scale (data centers)
  and small scale (embedded) contexts

Author: nikomatsakis

content/what-do-people-love-about-rust.md

@@ -26,7 +26,7 @@ The first is **reliability**. People love that "if it compiles, it works" feelin
 
 > "Rust is one of those languages that has just got your back. You will have a lot more sleep and you actually have to be less clever." -- Rust consultant and open source framework developer
 
-Another, of course, is **efficiency**, especially in data-center contexts:
+Another, of course, is **efficiency**. This comes up in particular at the extremes, both very large scale (data centers) and very small scale (embedded):
 
 > "I want to keep the machine resources there for the \[main\] computation. Not stealing resources for a watchdog." -- Software engineer working on data science platforms
 
@@ -152,7 +152,7 @@ For Rust to provide that "trusted tool that will help you tackle new domains" ex
 
 > "I was in favor of not using async, because the error messages were so hard to deal with." -- Desktop application developer
 
-> "The fact that there are still plenty of situations where you go *that library looks useful, I want to use that library* and then that immediately locks you into one of tokio-rs or one of the other runtimes, and you're like *that's a bit disappointing because I was trying to write a library as well and now now I'm locked into a runtime*." -- Safety systems engineer working on functional safety for Linux
+> "The fact that there are still plenty of situations where you go *that library looks useful, I want to use that library* and then that immediately locks you into one of tokio-rs or one of the other runtimes, and you're like *that's a bit disappointing because I was trying to write a library as well and now I'm locked into a runtime*." -- Safety systems engineer working on functional safety for Linux
 
 > "We generally use Rust for services, and we use async a lot because a lot of libraries to interact with databases and other things are async. The times when we've had problems with this is like, um, unexplained high CPU usage, for example. The only really direct way to try to troubleshoot that or diagnose it is like, *OK, I'm going to attach GDB and I'm gonna try to see what all of the threads are doing*. GDB is -- I mean, this is not Rust's fault obviously -- but GDB is not a very easy to use tool, especially in a larger application. \[..\] And with async, it's, more difficult, because you don't see your code running, it's actually just sitting on the heap right now. Early on, I didn't actually realize that that was the case." -- Experienced Rust developer at a company using Rust and Python