Thanks!

[MerryMarigold]

Ok. Am in a debate with friend about whether Thanks! and No Thanks! require an exclamation mark or not. I assumed they always have them, but she assumes it makes it sarcastic (especially in the negative No Thanks!). I automatically put one in when I write in a text message eg. Thanks for coming over! So, who is right? (I know, I know, overuse of exclamations is not good form, but I do love 'em).

They certainly don't require it. It depends on the tone you want to convey. I wouldn't say they make it sarcastic though I suppose it might depend on the exact context.

If I am sending a one word email with just "Thanks!" I would include one as it makes it (for me) more friendly and less terse.