Permadeath is a nice feature for co-operative completion of Fallout1/2 based on FOnline engine, so many players can play at the same time and it'll be harder to complete game because of permadeath, also it opens RP abilities and just adequate gameplay, no stupid rushes, suicidal actions, etc. Current FOnline, is MMO, permadeath will just make people grind more, you just raise your level by killing mobs and mindless NPCs, you don't have chain quests and main story-line quest, leveling happening in random encounters, it's just Quake/Unreal Tournament type gameplay, so there's no reason for permadeath.
Of course 2 days replication time isn't permadeath, it'll only raise number of alts, so you'll need to relog on another one while previous is dead. What for?