This is what my spreadsheet says:
Mind crack does not have wireless redstone, portal gun, NEI Plugins (but has NEI), Mystcraft, GravityGun, Compact solars...
DW20 pack is missing; Traincraft, Twilight forest, WRCBE, Gravisuite, Advanced solar's, Gregtech, Extra bees, Advanced machines, PetroGen, Voxelmenu, Rei's minimap...
My guess on the Ultimate pack is every single player mod and the ForgeCraft is every mutli-player compatable mod...
both mods (both theirs like 20 out all ready [I kid]) both new packs are great looking (going with the Mindcrack pack already started, DW20 sorry [again with this kidding business]...
Last note I love Voxel menu (music made with Minecraft blocks the best).. I seen the menu on slowpokes stream yesterday and was wondering what it was (not much of a builder so I passed up the Voxel box packs).