The poor exclamation point is always so wrongly accused of overuse. The exclamation point is often double or triple used (as if the first time it's applied isn't enough). Ever notice how people sometimes think that !! makes their point seem even more important or LOUD (we'll dissect the overuse of all caps some other day). I have important information to share for professional writers (or those who aspire to such status). Have you ever read a novel where someone used the exclamation point twice or triple? Okay, I will clarify my point. Ever seen a novel where it was acceptable to use use the period twice? .. you know just to say PERIOD -- PERIOD! Oh, sorry ... PERIOD!! Are you starting to feel enlightened now about overuse about the exclamation point? I have another one for you. You do realize that an exclamation point is not friendly with a question mark?! I see that one used all of the time as if it's correct, too. I'm sorry if you're feeling terribly sad about your last letter to your boss where you erroneously thought you were being impressive with your question (?) exclamation (!) combo.
Just remember in professional writing (or any kind of writing if you really want to know), don't use an exclamation point more than once. Don't combine it with a question mark. One more tidbit: use your exclamation points judiciously if you truly want to punctuate an important thought. Ever notice that too many sentences with that ole ! after each suddenly and with reason detracts and reduces emphasis?
But there are some important moments when lack of an exclamation point can end your relationship as it does in the classic Seinfeld episode. Elaine shrieks all too well, "You don't think that a person having a baby deserves an exclamation point?" So yes, use the "had-a-baby" concept when applying emphasis to sentences that deserve your point be made!