Most users will basically answer this, in a variety of different words being used to say that above. I won't buy Halo 5 blindly. If I did I'd have to blindly buy an Xbox One blindly, which I'd rather not do, even though I know I'll have to get one eventually. I just want bring up that, Halo 4 was a great game so I know Halo 5 will be good and a better game regardless.
I loved the campaign because the story again was amazing, the menu system was really good, Spartan Ops had a great story going, the Multiplayer was pretty descent, the music was amazing (the menu music especially was a beautiful piece), Customization was good, Graphics was awesome (nice and vibrant, not depressing at all), Forge was descent aside from the fact it was a copy and paste from Reach, overall if you didn't take Halo seriously it's a fun game to play. Of course I'm not going to mention the bad point, and also why I'm making these points about Halo 4, is basically to show that I have faith that Halo 5 will be a great game for Next Gen. But, obviously we haven't seen anything yet, so we can't speculate.