Having been a fair weather user of Google+, I think the new design, look and feel of the site will bring me back more often. In short, the Google+ re-design is heavy on utility and very comfortable on the eye (look at all that white space to the right of your timeline).
I also like the fact it’s much easier to start video hangouts (free video-conferences), and will be trying to use these more often for quick meetings with clients and contributors.
Another nice feature is the integration of Google’s Picasa photo editor. This allows you to quickly and easily clean-up any photos you add to your Google+ account.
There are shades of Twitter here too (probably why I like it so much), with a trends display and a suggestion feed of people you may like to follow (or add to your following circle).
All in all, it’s more functional, more familiar and feels more useful. Credit where it’s due, Google+ has designed something good. The video below explains in better detail some of the new features.