1) smileys should not be displayed as icons in URLs [require at least one whitespace around URLs to display smiley icons: URLs do not contain spaces]

2) it would be nice to have a smiley selector / menu / directory and not leave guessing to the user

3) maybe it would be wise to think about character-to-icon conversion a bit more, like not creating icons in the middle of words. this requires a bit of more advanced heuristics than search&replace, though. ;-)