• Declined:
• Generic /sequence command
• Spell Queuing
• Vendor value without being at a vendor
• API to retrieve DND or AFK status message from another player
• Finer-grained action button enable/disable events with some logic moved C-side
• /stopcasting <optional spell name>
• /swapgroup <playerName> <playerName | subGroup>
• Some way to iterate over the pet spell lists of pets you're not currently using (client doesn't have this information)
  
• What should be coming in Patch 2.3
• Eliminate the need for /stopcasting in macros that have multiple instant, non-GCD spells
• /petautocasttoggle
• /targetlastenemy, /targetlastfriend
• There is a new Frame member function: registered = Frame:IsEventRegistered("event")
• There will be a function to query which frames are registered for an event: frame1, frame2, ... = GetFramesRegisteredForEvent("event")
• Added the following macro option abbreviations for 2.3:
• modifier -> mod
• button -> btn
• actionbar -> bar
• equipped -> worn
• Added /targetexact
• Added an optional argument to GetItemCount() that will return the same value that GetActionCount() would for that item
• count = GetItemCount(item, includeBank, includeUses)
• Added a function for spells which returns the same value that GetActionCount() would return for that spell: count = GetSpellCount(name | slot, book)
• Added this API function: PickupItem(itemID or "item")
• /cancelform will be recognized instantly like /dismount is currently
• helpful = IsHelpfulItem(item) - Contains a right click ability that targets friendly units
• harmful = IsHarmfulItem(item) - Contains a right click ability that targets enemy units
• helpful = IsHelpfulSpell("name" or slot,"book") - The spell targets friendly units
• harmful = IsHarmfulSpell("name" or slot,"book") - The spell targets enemy units
  

• Note that a few spells are neither helpful nor harmful and can be cast on anyone.
• "The helpful/harmful thing is a little tricky, since what it's actually doing is checking the implicit targeting of the spell. Any spell that targets enemy units is "harmful" and any spell that targets friendly units is "friendly". There are a few spells which target any unit, which may be cast on any unit regardless of whether the unit can be attacked, can be assisted, or neither. There are also a few spells which target no units, where help/harm doesn't make any sense."

Via WoW Insider