One of the features I really like on Linux Mint is the "online accounts" that you can enable by clicking on your user name on the top right of the screen, which lets you integrate your Google (and other online account) contacts and calendar with the native OS applications.
I've been trying Ubuntu 12.04 RC2 on my System76 Lemur Ultrathin to see if I want to use it instead of Mint 12 on my main work machine once I get a new System76 Serval to replace my (still excellent!) three-year-old Serval, and I was a bit disappointed to see that the online accounts feature doesn't show up as an option when you click on your user name.
I was happy to discover tonight that it's in Ubuntu 12.04, just in a different place. If you go to the Contacts application you can add your online account from there.
Contacts seem to work fine, but what I don't yet see is how the calendar works (or doesn't work), and honestly I'm starting to think maybe the calendar functionality I'm seeing in Mint is by virtue of Evolution, which doesn't come preloaded on Ubuntu.
Having my calendar accessible right from the OS and having it pop up alerts is pretty darn handy so I'll have to dig into that further and see what my options are. I'm sure there's plenty of calendar applications available but the seamless integration is one thing I do like about Linux Mint.
If any of you Ubuntu users out there have suggestions on this I'm all ears.