Correct -- 0xfb20 through 0xfb4f are alternative glyphs for Hebrew characters. (I don't know what makes these so special that they need to be handled separately by the regexp processing code, though.)
This might be a good case for unicode character literals. Code dealing with unicode can be a nightmare to work with, even if you already know what those numbers are (arguably as this bug demonstrates).
Oh yes, Vim's code is anything but pleasant. I worked with it a decent amount several years ago when I was maintaining, for a short period of time, a patch that would add a terminal emulator to Vim windows.
It's nice to see terminal output at the same time as you're editing. Right now I'm working on a Rails app, so it'd be great to see RSpec failures while fixing my code--currently I either alt-tab between terminals or use a second monitor.
Also, sometimes you don't want to wait for something. `bundle install` can take a good 30 seconds...I'd rather not watch that!