8 player splitscreen will probably not be used much because there’s no way that system is going to handle 8 man splitscreen without a huge hit to performance.
Halo Reach disgusted me because the only time I ever played it was splitscreen with buddies, and the stupid piece of shit dropped the draw distance on player models so hard that in more open maps people were invisible even at medium (relative to the map) range. Nothing more fun than invisible snipers shooting you from every angle.