It's pretty much accepted that he is given his orders to kill Rand. And considering the "Let the Lord of Chaos Rule" quote.

I really hope that we see more of Taim in the next book, hopefully as much as we do of Mat and Perrin. Seems like he has a chance of being a credible villain, especially since the BT is the one area where Rand has displayed Forsaken-level stupidity. Taim needed to be put down long ago - right now, I think its clear that Elaida's foretelling will be just as she anticipated ("Rent in Blood and Fire", and we have no way of knowing who will come out the victor. Given that Taim controls most of the tower, and especially the strongest channelers, I tend to think that Rand will actually be the one running from that fight (he will strike them a blow but the part of the BT which will be destroyed will largely be his part - Taim and co will then move to a new HQ).