Rune Knight supposed to be some kind of magic-tank class. Main weapon will be great sword, has limited number of "runes" that can be used for offense (maybe big en-spell effects?) or defense (probably magic damage taken or AoE MDB buff).
Geomancer pretty much RDM without melee, as I understand. Focus will be on buffing allies, debuffing enemies. Apparently the job is going to receive its own line of enfeebles/buffs so that it'll stack with current haste/slow/etc and be more similar to auras than target spells. Similar to tactics, I think your auras can target either an area on the ground or center it around a single mob/player. The job uses a new "bell" weapon.