As I was working today, my Vim instance stopped responding completely. I ended up killing the tmux tab that Vim was in and starting a fresh one. I thought it was weird that Vim froze, but I just moved on. Then it happened again and I noticed what caused it: I accidentally pressed Ctrl+s. This causes my terminal (tmux is the culprit, I think) to pause accepting input. So it appeared that Vim had frozen, but it actually had not.
I recently switched from using Sublime Text 2 to Vim. Sublime is an awesome text editor, but I enjoy using command line tools and am intrigued by the massive following that Vim has. Also, three of the developers I work with use Vim and seem to know a lot of the tricks that make Vim indispensible. Although I haven’t gleaned much from them yet, I have found my way around Vim at my own pace.