Apple Updates iPhoto for Mac to Prepare for Upcoming Transition to New Photos App

the irony of their latest software attempts is that they are so simple that I already have a hard time understanding them

I had to read this 3 times. And decided that I agree with this. I think we have comprehension problems :)

I've been running the 10.3 beta and am enjoying Photos, used with DxO for important pictures. I think I'll pass on this update.

how you liking that Exposé and fast user switching?

Strangely, I like iPhoto, its interface and the whole style in which it was designed together with functionality as well as this of the iLife suite prior to iLife'13. I'm using iLife'11. In spite of minor issues it had I like it more intimate tone, it has spirit of Jobs's skeuomorphic approach. I bought my MBP 15" mid2012 in the end of 2013 factory sealed, with Lion, then upgraded to Mavericks, lived with it 1,5 years and then reverted back to Lion, also reinstalling iLife'11 and iWork'11. Feeling like returned home. Mavericks, though I still praise it for its newer features, wonderful iBooks, iMessages, Notification Center, seemed to me a bit hostile and was a letdown regarding the small functions that work seamlessly in Lion (QuickLook, Safari etc), but more so, speaking of accompanying apps such as iLife. iMovie crashing on launch was abhorring experience. iPhoto loaded slowly, so did Garage Band, while in Lion they launch immediately or at least much faster. Obviously it's not about hardware: an OS X released just after 1 and 4 months after Mac's manufacture date can't be too demanding for it. The software, and this maddening rush towards iOS&OS X integration (good thing itself) were the major contributors. Glad I returned to Lion.
Now iOS-like look of Photos injected fear into my veins: as much tolerable on iPhone and iPad as it is it looks weird on Mac's screen. As much as Yosemite looks glamorously so do Photos too (again, that's a very subjective opinion) and the impression of mine when I first saw this picture was that it's graphic card's failure resulting in zig-zags on a monitor. It's cold. It's primitive and oversimplified. iPhoto's retro beauty has gone freeing place for somewhat pesky and unorganized.

I know I may sound like I'm retrograde but I'm not criticizing all the novelties that Yosemite brought I like them! I just don't understand why to bring them it was necessary to fall back on flatness and over-saturation as something super modern and, hence, cool. Even 10.0 - 10.5 while also implementing some elements of flat design were much more realistic than the current version of OS X. "We need functionality in the first place, not glossy details that now look dated, old-fashioned" - so stupid and illogical. We? We who? Secondly, this "dated" look hadn't conflicted with functionality for years prior to the new fashion (and this is just about fashion, really, ain't it?) and suddenly someone decided to impose the new paradigm on masses, it's so religious, totalitarian and utterly philosophic. It doesn't have any rationality behind, just abstract aesthetical ideas (hi, Johny Ive!). That I may be correct is supported by the facts that even any iOS before iOS 7 had direct UI connection with OS X during all the period of its existence under Steve's reign.

The what?

Brand new features in 10.3!

Steve Jobs introduces Expose: https://www.youtube.com/watch?v=mAvHMDR1N3U

So I don't have to use iCloud at all with Photos? I don't want my data on the iCloud at all.

Nope none of it is a requirement and all three of the iCloud options can be turned off in the Photos preferences pane. I've got mine set up to use Photo Stream and iCloud Photo Sharing which are the old options that have been around for a while (iOS 5 for PhotoStream, iOS 7 for iCloud Photo Sharing if memory serves) and were in iPhoto but I've got the new (and still beta) iCloud Photo Library turned off.

It is the new iCloud Photo Library option that is the one that wants to upload your entire library to the cloud for syncing between devices.

Photo Stream is a rolling cache of your last 1000 photos that you can use to sync between devices and doesn't count against your iCloud storage and iCloud Photo Sharing is I believe a slightly revamped version of the shared photo streams from iOS 6 where you get to choose what to upload and share and with whom and does count against your iCloud storage allowance.

At least that is my understanding, but I've already been wrong once in this thread so.... ;)

Pancakes everywhere agree, flat is where it’s at.