John - In the admin console you can go to "settings" and "home page" to enable a landing page. Is that what you are after?
We have a widgetised home page turned on already. The use case was the guy who said he liked Yammer better than Jive ( ) saying he didn't like our Overview page and I was writing an answer telling him how to set his landing page to the Activity stream.
The issue is that on 5.0, a user could be told to go to General Preferences to set their chosen Landing Page. This is now deprecated (or broken? but I suspect it has been removed 'on purpose') and all they have now is the push pin - which is a tad 'subtle' - users may miss it. If I was voting I'd leave the choice on General Preferences.
My point about docs is that I went to the JiveCloud docs and searched for 'Landing Page', a 5.0 concept and found nothing - I was thinking of a section outlining features we have removed when the docs are ready for 6.0 as being useful.
In Jive for teams, that landing page is most often referred to as the "overview page" or the "home page". That might be why "landing page" isn't show up in the documentation, as anything might be considered a landing page.
Specific to Jive for Teams, we actually (by default) turned off that home page for a reason as users have become much more accustom to being taken directly into an activity stream instead of a more portal-like view with links and navigation. If the home page is turned off, that immediately pushes users to that stream and avoids any confusion around how to get there and how they can consume activity in Jive.
OK I do get all that (particularly re the Overview page) but please be careful about 'redefining' your language.
In 5.0+ General Prefs says: Landing Page: The first page you will see when logging in" and any of the stream pages can be made the Landing Page. But now in J4T you can only do this by pinning - as you have removed the preference setting we had in 5.0.
My suggestion re the docs is that whilst they talk about what you can do in the new release there is also a short section describing the stuff that has been taken away - I went hunting for 'landing page' as I could now longer see the setting.
Honest, I'm not trying to be anal about this