It didn't work that way for me when I tried it, but it's possible that the aforementioned bugs in Yosemite mean my experience is tainted! 95% of the time I can't get Airdrop to work - and this after 2 clean re-installs.Uhm, it's easier then it was before.
Previously, after taking a crap photo I had to erase it from the camera roll and then go in to Photostream and erase it from there and (if my Mac was on at the time) go and erase a 3rd copy from my computer.
Under the new system if I hate a photo I erase it once and it goes away everywhere.
That sure seems easier to me.
I might take half a dozen pictures of a subject and like only 1, but currently all 6 get uploaded - wasting my bandwidth, allowance and consuming my time to search out and delete the 5 that don't make the cut.
I'd like the opportunity to upload only the images I specifically choose to upload from a folder I designate! I could then easily delete what's left on my Camera Roll without worrying that I might accidentally delete the 1 good image of the half dozen - how hard can it be to limit Auto-uploads to folders of my choosing?
Get this: I found a new year greeting on the mobile web and saved the image to my phone to use on social media sites, That too has been copied to my photo stream and Mac before I could say "...temporary". It's beyond Stupid.
Imagine how much server space\money Apple could save if they didn't have to hold a copy of every single picture you'd taken, received or saved from other sources. The whole system needs rethinking IMO, and I pray that's what they're doing with the Photo's app.