I'm not keen on the typography on Yosemite. I hope I will like it better in practice, but it looks like the iPad, and I've had to bold that for legibility as it is. My belief is that legibility is best served by a fairly even and not too tightly leaded typeface like the one we have now, and like the one on the new federal highway signs in the US for example -- both the current Apple one and the new Federal Highway Administration one having been chosen through exhaustive testing and focus grouping for a reason. Unfortunately, unlike FHA with its safety inspectorate pushing for signage that motorists can read as quickly as possible, Apple have moved towards a "look" as opposed to usability. It's especially ironic given that as they're helping users by decluttering the graphics, they're hindering them by turning the text into a graphical element instead of, er, text. The new Apple font is like an overleaded Helvetica, prettier in graphical appearance but slower in practice to read, better than the current one from the point of view of having a font that looks good on screen and in ads, lousy from the point of view of actually using the computer. I can only hope they'll let us keep the old one . . . shouldn't be too hard if they're serious about a scalable UI and using vector support. But I probably should have taken iTunes 11 as a warning sign of where Apple were heading with this.
iOS8 I am very keen on. So much so that they *might* have done enough to get me to switch from Android, which I didn't think I'd ever consider. No real distinction on fonts here as both Apple and Google have fallen for the lure of the overcooked Helvetica, but in other areas it looks like Apple are serious about opening a real lead on Android for usability. Opening up the OS to extensions is fantastic; it solves one of the big problems for me on iOS, the lack of trace typing such as Swype. And in combination with the WiFi feature it might solve the other, the lack of user choice in tethering applications and configuration. If that one is solved as well, the iPhone will finally meet my needs without jailbreaking, and so I'll at last have an open choice between the two platforms. And just for kicks they went one better and added some decent configurability to the home page as well. So it's looking like a platform that can finally add competitiveness in features to its advantages in security and hardware.