I think it'll hover around $4 a gallon for the rest of the summer, then spike to around $4.50 for more the Labor Day travel season. Then come back down a little, but probably not down to $4.
While authorizing off-shore drilling won't immediately produce results, the price of oil is set by commodities speculators and they'll see an increase in overall production down the line as a result of the authorization and oil prices shouldn't be rising as precipitously as before.
Iran is looking at cooperating with The West re: its type of nuclear refinement process and this relieves much tension in the Middle East.
Come November, if Obama is elected, oil prices will rise sharply on anticipation of a pullout from Iraq endangering the region. If McCain is elected, oil prices will rise sharply as OPEC tries to put the squeeze on him for his support of domestic drilling by reducing overall production.