May 14, 2012 4:00 PM EST By Sara Yin
If you haven't yet, we've highlighted the top 10 changes you should know:
1. Some data is always visible: your name, profile picture, Timeline cover photo, network, gender, and username are always visible to all Facebook users. However only "Public" profiles (the default option) are listed in search engines; click into Privacy Settings/Applications and Websites/Edit Your Settings to tweak this.
2. Careful what you write: Your messages are never deleted, not even when you delete your account. This is because they are stored separately from your account, since other people see your messages. They will continue seeing messages that include you even after you've deleted your account—standard stuff for any messaging platform, but something to be aware of.
3. Facebook notes your "Likes" and brands mentioned in posts: Facebook trawls your posts for brands, which may lump you into a target category that is sold to advertisers of that category. Facebook gave the following example: if you 'like' Pages that are car-related and mention a particular car brand in a post, Facebook might put you in the 'potential car buyer' category and let a car brand target to that group, which would include you.
4. Post no evil: Facebook may intervene if your post suggests you are going to harm yourself or harm others. Previously, it only shared information suggesting fraud and other illegal activity, or threats to Facebook itself.
5. Facebook can transfer data to others' devices: Once you've shared anything on Facebook, your contacts can save this information on their mobile devices. Don't post unless you're okay with a friend saving it to his or her smartphone.
6. Ads using data: Forbes' Kashmir Hill noted two key changes to how advertisers can use your data. First, Facebook removed the 180-day limit it keeps data sent from advertising partners. Instead, Facebook will retain the data for as long as it needs to serve you ads.
7. Your Facebook data is used for ad targeting outside Facebook: Hill also notes that Facebook has made it clearer that it uses information you share on Facebook to serve you display ads outside Facebook.
8. Apps keep your data even after you delete the app. ArsTechnica pointed out that deleting an app doesn't delete the data from their servers. To do that, you have to contact the app maker directly.
9. California residents: You lucky folks can request what information Facebook is sharing with third parties for direct marketing purposes. Also, Facebook can't share your information without your explicit permission.
Ah, the price of free.
You can also obtain a copy of all the personal information (photos, messages, videos, status updates) you've shared on Facebook, plus an expanded archive with your friend requests and IP addresses you've logged in from. I requested my file and within two hours, Facebook sent me a download link for a 72MB file (my previous requests went ignored).
On Monday, Facebook's chief privacy officer for policy, Erin Egan, answered users' questions about the privacy update. Nothing new was revealed, according to my co-worker Chloe Albanesius, but Egan gave three reasons why the updates were made: first, to comply with a pledge to the Irish Data Protection Commissioner, which has long been on Facebook's case over its facial-recognition technology. Second, to include new Facebook products launched since the last policy update in September (Timeline, school groups, etc.). And third, to make everything more transparent to users. For instance, you'll notice little light bulb icons with tips on how you can better protect your privacy.