In the World of Warcraft Forum there is a very nice post about the coming changes to Macros in World of Warcraft 2.0 Patch. If You are using Macros You really need to look into this. Due to the nature of the WoW Forums that seem to drop Postings after a while I have attached a Text file as download.
There are changes that make it easy to either cast Ambush or Backstab dependant on Stealth in a simple macro. You can also set a /castsequence for spells, that will cast the spells one after the other each click. The handling of stances, buttons and targets equipped items are much more convenient.
Cast Ambush if stealthed else Backstab:
/cast [stealth] Ambush; Backstab
Mount if You are not mounted and outdoors:
/use [nomounted,outdoors] Black War Steed Bridle
/castsequence Corruption, Immolate, Curse of Agony
Cast Greater Heal on a friendly target, or Smite if the player is in combat, or Mind Flay if the player is not in combat:
/cast [help] Greater Heal; [harm, combat] Smite; [harm, nocombat] Mind Flay