Before you get too excited at the headline, let’s clarify what Monster Hunter Frontier is- it’s an MMO based on Monster Hunter that has thus far remained Japan and Asia exclusive. Monster Hunter Frontier has been made available on Xbox 360, PS4, PC, and even PS Vita- their existence on a platform is in no way indicative that mainline Monster Hunter games will also follow on that platform.
With that out of the way: a new rumor (via NeoGAF) seems to indicate that Monster Hunter Frontier 2 may be in development at Capcom Korea for PlayStation 4 and PC. The new MMO would presumably be updated for fourth generation Monster Hunter mechanics (the existing Monster Hunter Frontier is based on second generation mechanics), and is apparently going to be built on Unreal Engine 4.
If this is true, then chances are that it will be announced at the Tokyo Games Show, and that it will never come to the west, just like the first game. We’ll keep you posted either way on what happens, though.