As with all OS X releases, Apple has added plenty of new features. How do these features rank in terms of usefulness and likely wide adoption? Which ones will become signature features? I'll size them up from my own perspective.
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New OS X features exist in a spectrum. The OS change can range from a under the hood improvements to UI cleanup to improving functionality to an outright new feature. Sometimes the feature is minor, and sometimes it's a blockbuster.
For example, OS X 10.9 Mavericks brough us App Nap and Compressed memory under the hood. Contacts and iCal brought a new look and feel. Multiple Displays tweaked and improved the functionality. Calendar brought integration to Maps. Finally, Apple brought Maps and Tags to the OS.
Sometimes, the improvements just sort of glide by without too much focus, and they're there when you need them or go look for a solution. They're so obscure, they need a TMO Quick Tip. However, sometimes a new feature becomes the signature feature of the release.
Yosemite's Major Features
Here's a look at the interesting features of OS X 10.10 Yosemite. I'll grade the features from F to A based how useful I think they'll be (for me anyway) and how likely it is that it will become a signature feature. [The list is in no particular order.]
1. Phone calls (A). I think this will be a game changer for several reasons. My enthusiasm is based around the idea that when my iPhone rings, and it looks like I'm going to be on the phone for awhile, I ask the caller for a second to attach a headphone. Alternatively, the sense of separation and audio quality of the speakerphone isn't so great. Using the first class Yeti microphone and speakers of my Mac is the way to go.
Plus, when I'm in my recliner with the MacBook Air writing, and my iPhone is in another room, charging, I won't have to kick my cat off my legs, my MBA off my lap and go running. It'll be awesome.
2. SMS messages (C). I am not a huge user of SMS. I do use iMessage occasionally with other Apple friends, but I figure an SMS message from a non-iPhone can wait until I get to my iPhone. When I'm writing on my Mac, which is most of the time, I try to avoid distractions anyway.
And that brings up larger issue. When I'm working, I hate distractions. I have "Do Not Disturb" turned on for Notifications during writing hours. I do listen to iTunes for mood music and monitor our TMO chat room, but that's about it. And so I see SMS messages on the Mac as a pleasant and distracting tool for some, an annoyance for others.
3. Handoff (C). Having said all the above, you can probably imagine how I feel about starting an email on a Mac and continuing it on an iOS-device. I think that's just a sample use-case, and the real advantages will evolve and come to light later. It doesn't light me up.
Next: Features #4 Through #8.
Yosemite Features #4 Through #8
4. iCloud Drive (A). It's about time Apple made iCloud more useful and transparent as a storage medium, not just a sync service. Aside from being mindful of potential privacy issues, I think this is going to really take off. Unlike iDisk, however, this time Apple will have to stay the course. This will be too important for Apple to someday say, "Sorry. iCloud drive is shutting down."
5. SpotLight & Search (A+). This will probably be the major, signature feature of Yosemite. For some background, see "Apple Lays Groundwork for Disrupting Google’s Search Business."
Apple appears to be focusing on the idea that data is not branded. You don't go to the Weather Channel to get weather. You don't go to Google to search for an article on red wines. Instead, you go to Yosemite search, and it figures out what you want and how to get the information. That means that search (and Siri) don't have to be forever tied to a capricious data source. This is a game changer and an overt shot at Google because Apple isn't trying to monetize Yosemite search. So far anyway.
6. Mail attachments (A). It's about time Apple took ownership of this problem. If an attachment is too large for your ISP's email service, the Mail App will send it through iCloud. If the recipient is using Apple Mail, it's transparently attached. If not, they'll get a URL to click on and download the attachment. This is going to eliminate an email headache average users have had for years.
7. Mail markup (B). Annotating attached images is something I do fairly often, but I can't see that its going to really pick up steam. It's one of those features that'll be forgotten until you need it, then use it casually, appreciative that it's there.
8. AirDrop with OS X and iOS (A). I can't wait. The business of having to use iTunes App sharing or emailing photos from my iPhone to my Mac is, frankly, obscene. While Apple says, "So with just a few clicks on your Mac, you can take a file from any folder and use AirDrop to send it to a nearby Mac or iOS device." While that doesn't mention iOS to Mac, I know someone who has tried it, and it (almost) works in Beta.
There are more features, like Notification widgets, some Safari changes, and a visual facelift. But I'm out of space, and these items are subjects for another day.
The bottom line is that I'm very excited about Yosemite. The new features look to be things I'm going to be using all the time — in contrast to some things in Mavericks that I've never gotten around to a dedicated exploitation of, like Tags. This feature list, more than ever, shows that Apple is attacking our modern day, fundamental problems, making life with Macs and iOS-devices better and more integrated, yet preserving the fundamental character of this fabulous Unix operating System that we all have come to love.
Best of all? OS X Yosemite will be free.