Picasa seems unnaturally safe in this model. It's also stopped iterating generally and Google's acquired a totally separate mobile app for photos (Snapseed). And Google really doesn't make any material amount of money off Picasa either.
And Linux support (which was only through Wine) was officially dropped.
Even before the recent spate of services being shut-down, shortly after the Linux support was dropped, I moved Picasa to a kill list and started migrating what I was using it for to something else (Dropbox for storage and sharing).
I presume it's going to be killed, to me that's what the product state signals.
Dropbox also has photos now, when you log in on the bottom left there was an opt-in for the beta testing. It's really nice compared to Picasa/G+'s "2 different photo services but not really" design.
Yes, Picasa's rating seems wrong enough to me that I called it out in the discussion as probably wrong. (Not sure how one would improve the model... how do you objectively rate or quantify something like 'stopped iterating generally'?) And it make not make 'any material amount of money', but it is still selling advertising and whatnot on Picasa: https://support.google.com/picasa/answer/166073?hl=en So the binary variable for 'profit' gets flipped...
Snapseed is not doing any better, though. IIRC Google already shut down an app for Snapseed.
I think Picasa might wind up being merged totally into Google+, although by my established criteria that would not count as a shutdown.
You mentioned in passing that you have a feeling that Picasa isn't surviving for long due to it's "old-fashionedness".
Considering how important "usefulness" and "usability" are by now, maybe add a criteria along those lines - how large is the "your mom uses it and likes it" factor, how "contemporary" are the UIs, how much effort puts Google into polishing it (it does a lot with G+ and Gmail for example) - something like this.
Another criteria could be "level of integration" - how much can you use a Google product as a standalone project or how deeply connected is a product into another one (e.g. Picasa used outside of G+) - which might in the end indicate not a direct shutdown but a product's dissolution into another one.
I'm not my mom, so I can't do that! Such subjectivity is something to avoid in an analysis like this. And 'level of integration' seems just as hard to assess.
"Picasa" the desktop app maybe, but I think the reason Picasa web albums/API lives on is that it provides the backend for Google+ Photos and they don't want to break existing apps using that API just to rename it, so continue to build stuff on it. Most recent example would be the Photosphere viewer API they just released: https://developers.google.com/panorama/web/
