Maybe Picasa albums should be treated the same as Google Docs documents: they're private by default, but you can share them with a group of friends or publish them.

Renaming an album is a faster option to re-hide an album.

And I agree with Ionut, a system where you can select who can view your pictures would be even better. And what is the difference between a document and a picture? Why can i synchronize folders with pictures and not so with documents?

Sometimes I wonder if google has a master-plan, or if its just a group of people making stuff and then going off to the next project. And I hope the new project is an integrated version of picasa/docs/mail/google-drive something something.

(Thanks Wouter, I added an update!)

Wouter
I think Google has a master plan, just not a very organized way of achieving it. People seem to work on a project, complete it to some level of satisfaction, and then leave it alone for a while. Of course, there are bug fixes and back-end updates, but not much innovation. Then someone in Google notices a stagnant project and says "this could be lots better if..." and eventually we have a flurry of innovation again.

I think this is exactly what happened to Reader, Blogger, Picasa + Web Albums, Docs, Finance, and GMail.

I sincerely wonder about forgotten products like Dodgeball, Jaiku, Grandcentral and friends.Nobody seems to love them.Then there's projects like Print, Youtube, Google Video, Froogle, and Base. They get minor changes and updates often, but it's hard to see what Google is actually going to DO with them. Maybe there are "big" relaunch updates on the way for some of them (like iGoogle). Who knows.

Products that are constantly improved like Android, AdSense, Search and Maps are potential and actual cash cows, so of course they get the most G-Love.

Well at the very least,i can comfort myself that i don,t have any compromising pictures,cos if i did who knows when you can,t gurantee the privacy of your pictures.

If you have something you don't want others to see do not upload to the web, Period.

Just to show how fallible the system is I am ron angel but NOT the ron angel referred to when you click on the name to see who posted!

Any references for this issue available??

Juha-Matti, after verifiying this hole a while ago in a test Picasa Web Album* of mine I sent the issue to securitygoogle.com and others on August 29. After Google's auto-reply there was also a templated but apparently human second reply which said "We appreciate your cooperation and discretion on this matter while we are looking into it. We will follow up with you soon." Google Security never followed up on me on this, but just recently I noticed that URLs were no longer linked in my test album.

* http://picasaweb.google.com/philipp.lenssen/ARenamedTotallyUnlistedAlbum?authkey=5gg6kWGIRcU#5239972519191427426

So, that mean if I have a private album, and I've never shared it with anybody, it's still safe, right ?

Picasa has public and unlisted albums, there's no private setting at the moment (though if you uncheck the "public" option you may be convinced to believe it must therefore be "private"). But I don't know of any other holes at the moment, so as far as this hole is concerned, it's fixed now for future uses (if you created your unlisted album after Google introduced the authentication key, that is... before, people were able to just guess an album name to get in). Note that for this what it took was either you or a friend creating and clicking on a link in the comments to a photo. Also note that if someone already found out the authentication key previously through this method, then that is still not fixed, it would only be if Google would issue new authentication keys and break old permalinks; Google could check which albums received URL comments and issue a new key for those and alert users, but I don't think they did that. To fix that on your end you can rename the album.

Fine. This clarifies the situation, additionally to users not writing their first Picasa comment yet.
But it's sad that Google's security team never replied with a more personal message.

The best would be to have more settings and be able to tell Picasa wich people you allow to view your albums.
I don't understand why this is STILL NOT a feature :'(. . . Actually it's not cool at all to share album with my friends :((.

And when will come the next "GB extension" :D ? It has increase xx -> 250 MB – > 1 GB every previous year near september. I 'm waitting the next one to upload my photos (7GB for mails and only 1 for photos ? Hey, wake up Google :). . . . .)