Current rules don't cover this topic, but I gues that card with spellbind and channelling is spending it's mana (and than mage's mana if required) for casting bound spell (simmilar to spawnpoints and familiars).
If yes, think of Thoughspore as of Mage/Elemental Wand + channelling + it's own action + it can be in the other place than mage, but it is easier to kill, limited to only one 1-2 level spell and costs 3 mana more.