Oz Communications demonstrated picture messaging through their mobile IM client at CTIA in New Orleans. According to the businesswire press release:

The OZ Mobile IM Client with AOL’s new Instant Pictures feature enables AOL(R) members and AIM(R) users to use their mobile AIM service to send instant pictures to friends and family members using mobile devices by simply inserting an image into the AIM(R) conversation. Recipients see a thumbnail image on their mobile AIM(R) screen that they can click to expand. They can then reply with their own mobile Instant Picture for a fun picture sharing experience with anyone and everyone on their AIM(R) Buddy List(R) feature

It seems that T-Mobile, Cingular and Sprint in the US are customers of theirs. Given that, we have email and IM that can easily deliver pictures across carriers. Plus, I’m assuming you can send the same pics to IM users logged in from their desktops.

Where does this leave MMS, which can’t operate cross-carrier at all now?

Yes, MMS has sound and animation. But I think the tedious process of composing a fully animated and sound-enabled MMS outweighs the draw. However, the process of sending a picture through IM could actually be easier than sending one to flickr or textamerica if you already have a chat session open. No email address to fumble with.

Perhaps the moblogging sites could use IM as a new input mechanism?