Interesting, I had not heard of Foundation before, and am interested in checking it out to see how it does with the few things that annoy me about Bootstrap. So appreciate the pointer.
But when I go to the Foundation web pages... I've clicked like 5 times, have managed to get to the Getting Started page, and I still haven't seen any code examples of how to actually use it. Note that the Bootstrap docs start with and are centered around examples; it _starts_ by telling you how to install it and start using it. Every 'feature' element on the home page is right next to a code example showing how to do it.
I think Bootstrap's documentation is actually a huge part of it's success. If you're wondering why Bootstrap caught on where Foundation didn't, I think that's probably part of it. Foundation's docs _look_ as pretty as Bootstrap's (which is a good sign given the nature of the products), but they aren't done as well for getting people to dive in quick or overview of how the code actually works quick. Writing good docs is a skill of it's own, and whoever does it for Bootstrap has definitely got it. You can get started with Bootstrap _so_ fast, because the docs are written with that goal in mind and achieve it.