Incidentally, RVM is another software package with a curl-based install :)

$ bash < <( curl http://rvm.beginrescueend.com/releases/rvm-install-head )

And npm is another popular one. I'm not sure if the multiple examples helps your case or tptacek's though. (That is, we all seem to be getting more and more comfortable with this style of installation.)

tptacek has a good point that you shouldn't just trust any old curl-based install, but I think that really applies to any install of any kind. I think you have to consider the source of any software package, it's not something specific to this particular method.