I have added support for Spellsurge to CasterWeaponSwapper. Now you can have your main casting weapon set, and a Spellsurge mainhand/offhand combo. The Spellsurge set will be used until it procs, then will be swapped out for 50 seconds, and so on.
http://www.wowinterface.com/download...onSwapper.html
I did run into one difficulty. When you get Spellsurge from your weapon, you get the event CHAT_MSG_SPELL_PERIODIC_SELF_BUFFS that says "You gain Spellsurge." You also get that event for the mana ticks from Spellsurge, with "You gain 10 mana from Spellsurge."
However, you get that same event when, for example, you are healed by someone else's Renew. So I suspect that you'd get the same event from someone else's Spellsurge too. And I can't find anything specific to the events or their text to indicate that the mana is coming from your Spellsurge.
So what I am doing for now is assuming that if I see the "You gain Spellsurge" event, while your Spellsurge weapon is equipped and cooled down, then it is from your weapon. So it calculates the cooldown time as 50 seconds from now, and queues your other casting weapon to be swapped in for the next cast.
If anyone has a way to clearly tell whose Spellsurge is whose, I can add it, but for now I think this heuristic is pretty good.