This is my first posting made from my iPhone to my SquareSpace blog. Of course, I can't possibly type as fast on this keyboard as I do on my PC, but if you are on the road and you want to put something up, this seems pretty simple to do.
It provides a rolling list of all your categories, you can adjust the publishing date and time, and you can add pictures on the fly either from your stored images or you can take one on the fly. One drawback on the photos, I don't see any formatting capabilities like I have with LiveWriter. I know, picky, picky.
You can save your post as a works-in-progress or post it up very simply. And, if you have multiple sites you can set them all up and have them handy. I'll work up some screen shots when I do my follow up.