It has been discussed and from what the team have said it will be released when a new and improved version of Palringo is ready and polished.
I personally would like to see the pictures handled similar to facebook where the top corner would display a small picture of the contact and you couldn't see your own while messaging. With a Pictures option in the settings section of Palringo which would allow you to select a picture from your iPhone and also allow you to disable Display Picutres.
With group chats, I'd like to see no icons for anyone since they wouldn't be needed in such conferance settings.
I suppose the best answer is "When it's ready".