Okay, I went over the updates on Wizards of the Coast and discovered that the Infernal Wrath power has changed from what it was in the Player's Handbook. There's one part that confuses me: 

"Infernal Wrath 
Encounter - Fire
Free Action 
Close burst 10
Trigger: An enemy within 10 squares of you hits you
Target: The triggering enemy in burst
Effect: The target takes 1d6 + Intelligence or Charisma
modifier fire damage." 

I always understood that Burst mean every enemy, but this power seems to violate the use of the keyword Burst. I understood it to mean that a burst covered a target square and the surrounding squares (including diagonal). Say that Scorching Burst has an effect area of a 3x3 square centered on a target creature no more than 10 squares away from you. Is the Close Burst ability different? I had understood it to mean that it meant every square around you within the Burst gets affected simultaneously (as with the Prismatic Beams Spell). Can a Burst target only 1 creature like the revised Infernal Wrath power suggests? I just want to make sure I use it correctly. Thanks.