As mentioned before the goal with this client version is to be cross-platform compatible with all major platforms including mobile and desktop. Within this version, the new navigation elements are starting to take shape, the navigation will allow players to switch between various screens by selecting the appropriate Icons are the top. This navigation works the same with mobile touch screen, mouse/keyboard as well as the joystick( currently joystick is not fully implemented ).
This client also has the ability to view the list of available game rooms but does not yet contain the ability to join a game room.
And yes this finally has the ability to join the World! but before you get too excited there isn't anything else it can do in the World part other than chat, however, you can see the World navigation is different than the Lobby navigation and rightfully so as the World has more navigation requirements for all the different screens that need to be illustrated.
As development continues to move forward there will continue to be more changes. One of the changes that you may have noticed is the different text input component for sending in-game chat messages. This will be an important component in the future that I will not get into at this time but it is a multi-purpose chat component.
I hope you like the new navigation now that you get to see it and please feel free to provide your thoughts on it as well as let me know if you have any questions.
Have a great weekend :)