[laundrysheet1]

Can someone please clarify what justifies the 3.2 -> 4.0? I don't see a big change, isn't this more like a 3.2 -> 3.3?

[bcardarella]

Rails 4.0 drops support for Ruby 1.8.x which necessitates the major version bump.

[melvinram]

From what it looks like to me, it's not so much about a drastic new feature set but rather about trimming down dramatically. You could argue that it really should be like 3.2 -> 3.3 similar to OSX Leopard -> OSX Snow Leopard. I think they gave it a full version upgrade because it WILL (not might) break a lot of apps. That's my interpretation. I might be wrong.

[wynst]

Ruby 1.9.3+ justifies the major version bump

[technojuicy]

Part of it could be PATCH replacing PUT.