Rectangular mark mode is really awesome. It makes working with rectangles a lot easier. It is now so well integrated into my workflow that I'm really annoyed when I have to use an older Emacs version.
I used BRIEF for a few years until I moved away from strictly Windows development so I moved back to Emacs. Columnar editing was something I missed so much! But now that I've been away from it, it's hard for me to recall what I used to use it for.
Occasionally I do find that I wish I had it, but I remember feeling so crippled without it for a long time! So, can't wait to get back into it again now that it's available. I think it's one of those things that you start using it and find more and more things to do with it as time goes on. Just my $0.02 anyway.
I can already kill (C-x r k), yank (C-x r y), replace (C-x r t) text in rectangles, insert text after the rectangle (C-x r z) or at the beginning of all the rectangle lines (C-x r a) or their ends (C-x r e).
What else is there?
http://emacsredux.com/blog/2014/01/01/a-peek-at-emacs-24-dot...
I'm curious to know which things are easier for you with 'C-x space'.
The annoying thing about C-x space, is that it used to do something completely different (set gud breakpoint), but I digress.
Really? Upon reading the release notes, I was excited that I'd probably be able to just use commands like C-w or C-x u to act on rectangles. Sad to see it won't be the case.
From the manual: The command C-x C-k r (apply-macro-to-region-lines) repeats the last defined keyboard macro on each line that begins in the region. It does this line by line, by moving point to the beginning of the line and then executing the macro.