I brought and installed 4 Pro today and my initial reaction is very disappointed. Keyboard shortcuts have been changed - well frankly the whole intreface has - its like a different raw converter all together. What made 3.7 so good was it was an elegant, intuitive and simple interface. 4 seems to try and cram everything into the different "tools" making it very cluttered (now called "tabs" which while being more acurate indicates the level of name changing for different functions, which is very irratating). 3.7 required the user to use preferences, nested functions in drop downs etc ; now all of this seems to be cramped into the tabs. I have to learn how to use this because i'm sure at sooner or later the photographers i work for will be using it, but I really despair at the way companies fiddle around with something great because they feel they have to at the expense of users - if it aint broke etc... rather like mac removing matt screens as an option for macbook pro (unless you fork out two grand for a top of the range one). Incidently, have gone a little off topic, I am pleased that 3.7 still runs fine independently on my mac pro - i was thinking i was going to have to start messing around with externals so i could run both...
: )