No. Their version of smite evil is exactly what is listed in the simple template. They just get their Cha mod to-hit, and their HD to damage.
As Cheapy indicated. Little less powerful than an actual Smite.
Special Attacks: smite evil 1/day as a swift action (adds Cha bonus to attack rolls and damage bonus equal to HD against evil foes; smite persists until target is dead or the celestial creature rests).
Honestly i wish it was just a Smite ability. I plan on playing a malconvoker Summoner soon and Im pretty sure the "Smite Good" ability of infernal with never come into play.
Does the celestial creatures attacks count as good aligned?
Only if the celestial creature has the Good subtype.
EDIT: That is to say, the Celestial template doesn't grant good-aligned attacks, but having the Good subtype does.