Hey Mike
Thanks for spotting the issue - I have fixed the documentation on the wiki.
I've been working on Spore in several different iterations for about a year. It started out as a project that would easily allow me to port a Flex project using amfPHP (a very popular Flash-PHP library) to HTML5 / JSON.
I'm the kinda guy that likes to build things to understand them deeply, so I decided to roll me own. There are several other solutions out there like RESTler, Silex and Symfony - but I decided to write my own because the other options were either too complex (Symfony), lacking in features or unnecessarily bloated. Spore is very lightweight, fast and simple - thanks to its Slim base.
Thanks for the question!