In OS X Yosemite's introductory conference Apple boasted of a brighter and cleaner UI which included translucent windows, an optional dark mode and the key change for me being the switch from Lucida Grande to Helvetica Neue. Now don't get me wrong Helvetica is a good typeface I am not dissing it, however I don't see the reason for the change. For a start Helvetica is not the best typeface at small point sizes because its terminals are tightly confined and curve back into the letter and so they have little whitespace amongst and inside the characters. And so because of this Helvetica looks very dense at small point sizes when you compare it to Lucida Grande which is much more open and its terminals have breathing space. This dense appearance Helvetica has contradicts Apple's open, bright and clean UI. If they wanted to change the font to give OS X Yosemite a fresh look they should have done more research into the work of Erik Spiekermann and other specialist typographers, they could even collaborate with such people to create an exclusive typeface of their own.
