It looks like Xat is preparing a big block of new smilies. Right now, in the smilie list, all we see are blank placeholders where the new smilies will eventually be placed.
Hovering our mouse over each space gives us the following new Xat smilies:
angel, susake, vegeta, loser, rockon, palms, thumbsup, thumbsdown
Among the blanks we also still see “chew”; which has been blank for sometime now.
Update May 18th: Here are the new smilies that were leaked over the weekend.