It's pretty simple to set up and use aws (simpleDB in particiular) to accomplish the same goals (back end support for simple mobile games) without having to write server / database code.
I mean, really. Read what they offer before commenting.
For what it's worth, my question was not intended to put down Parse in any way. I've recently been using simplDB and their ios SDK and so was genuinely curious how Parse was better / easier since after reading it, a lot of the code looked like the same basic code I used to set up and use simpleDB in my project using the ios SDK from AWS.