Here's the 2.5 Preview page
http://members.mh-frontier.jp/preview/season2_5/
I'd translate some of it...But my computer is effectively dead. I'm posting through a snowstorm of artifacts from my dead graphics card and won't have a new one till next Friday.
However, there's a HR51+ Red Espinas coming, which seems to be the main point of this update and there's new SP armors, the new マイトレ feature seems to be some sorta shop?...New Espinas head and rug for your gallery, new Poogie outfit...and my computer just got worse and I can't see the screens anymore..lol...