Widget Visibility is the simple, yet powerful, feature that is used on WordPress.com today. There are plenty of other stand alone plugins that offer similar functionality. Widget Visibility is a feature that was originally released just on WordPress.com, and now made its way into Jetpack for everyone to enjoy.
The functionality is very basic, “show” or “hide”, then choose which template view is active: category, author, tag, date, or page. I’m actually quite shocked that “post” isn’t an option (or “single”). Maybe there is something I’m blatantly missing to show or hide on a single post (like the one you’re currently viewing here on WPForce.com).
The other feature in Jetpack 2.4.0 is WordPress.com Connect. By now you’ve hopefully heard of services like Facebook Connect or Google+ Direct Connect, both offering ways to login to a website through another site’s authentication. This is how WordPress.com Connect works. You can allow your users to first login to WordPress.com, then using those credentials, allow access to your website and not force them to register again.
I haven’t tested out WordPress.com Connect yet. I have a hard time imagining that it’s ever going to have remotely the same Internet-wide usage as Facebook Connect. There is a limited amount of data that website owners can get out of WordPress.com Connect, so there isn’t much of an incentive for site owners to use it. Looking forward to see some usage stats on WPCC in 6 to 12 months down the road.
One aspect of Jetpack that I dislike is the fact that you are required to connect your site to WordPress.com before using any feature — including Widget Visibility. In case you’re the same mind set as me, you can check out Jetpack Slim, which is a feature-delayed version of Jetpack, without some of the WordPress.com-centric features.