What do you shoot with right now? If you have camera with a SD card slot you can use the eye fi card like I do and have the photos go immediately to your phone and you can post them up on instagram, facebook and twitter right then and there.nice for some.. but i would rarely use it.
The first thing that jumps out at me is my constant frustration with having to get home before I post photos. I go shoot a protest or rally (like I did this past Saturday with the Chicago Teacher's Union strike rally) and while I'm sitting on a train twiddling my thumbs, AP, Getty, and everyone with instagram is posting first. If the phone app really works quickly and isn't too buggy it would be great to flip through 500-1000 photos and rate my top 10, transmit my top 3 via e-mail to an editor, then process the others for a slideshow in the evening.
Typically, wire service photogs crash in a hotel or starbucks, but occasionally you're out somewhere with limited access to WiFi, and this kind of thing (tethering wirelessly to a smart phone) just adds one more option.
It would just be a workflow process improvement for anyone shooting on a deadline or from a remote location with no wifi.