First off, let me say this; the more transparent a user script is, the better, in my personal opinion. Google+ Tweaks is just that; transparent!
My favorite feature this script offers expands the Google+ feed to both edges of the browser. I'm not sure exactly why so many websites today, in what I thought was a time when most people use widescreen monitors, opt to keep all of their content scrunched in the middle, but this script fixes that without a problem.
Other features include the hiding of components on the left and right sidebars, adding a few shortcuts, namely for muting posts and mentioning individuals in posts, and the option to make the sidebars and the whole top of the page - including the Home, Profile, etc tabs, the Google Bar, and the search bar - "stick" as the user scrolls down.
Google+ is, as I mentioned, not released to the entire public yet, as it is still in Beta testing and development. Thus, the formatting of the entire site is constantly changing, which affects, and will continue to affect this script's performance. The author has, since I've been using the script, kept a good record of updating fairly quickly though, so always check back when the script fails.
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