Just a day after being released to the developer community, macOS Mojave 10.14.4 beta 3 has now been released to those registered in the Apple public beta program. If have a device registered in the program, the update should be available now. You can go to Settings>Software Update on your Mac to check for it.
As mentioned on the developer release of this beta, this release is primarily focused on being a maintenance build, there are some new improvements in this release. First, Apple News will be available to those in Canada after the release of macOS Mojave 10.14.4. Canadians will be able to read articles in both English and French. Second, Touch ID support has been expanded in Safari in 10.14.4. Now you can use Touch ID to autofill fields in the browser.
As of now, there is still no confirmed release date of macOS Mojave 10.14.4 to the public. That is normal for Apple who does not publish release dates. That said, based on historical beta cycles, we should see this release go to the public late this month or early next. This, of course, is dependent on a number of factors including if a major bug is found in the beta cycles. Typically, Apple releases four-to-five beta builds of a “dot” release such as this in the beta cycles.
Average Apple Guy, and Apple themselves, does not recommend installing beta OS builds on your production Macs. Any bugs in the code could cause degraded performance or data loss. It always best to install beta builds on non-product devices.