Its not just saving on brackets; you get a few other benefits like not worrying about closing or improperly nesting tags. It also slightly changes your mindset

Its not just saving on brackets; you get a few other benefits like not worrying about closing or improperly nesting tags. It also slightly changes your mindset from, "I'm just cranking out markup," to, "I'm building out a DOM tree," which turns out to be great thing for Javascript development. ERB/"classic" markup still have their place though. HAML is a real pain if you need to crank out a web page that's heavy with content. I use both ERB and HAML in most of my Rails projects; HAML for the more "application/javascript"-heavy parts of my apps and ERB for the content-heavy pages. At a glance, I don't see the value in jabs. While it might make code more compact, it doesn't seem to be as clear to worth with as HAML & SaSS. Trading clarity for compactness is a trade-off I reject.