If emoticons are good, emojis are fine too. They convey the exact same thing; they just look different.
That’s the problem though. They look different. Emoticons blend in perfectly with a line of text. Emojis don’t. Their disgusting contorted yellow faces steal your attention away from the text. Non-colored Emojis (like this site has) are a little better, but I still don’t like 'em.