Our Beta Playtest doc is in editing and formatting as this update is being typed. No matter it's state, we'll have it out to at least all backers in one week. Depending on how long Paizo takes to process it, the beta doc will be posted as a free download to Paizo.com shortly thereafter.
The purpose of our playtest is to fine tune the game before publication. So, we're going to need your help! Start scheduling playtest sessions for your holiday break, if you can. And please go to http://puresteamrpg.com and sign up for our forums, so you can provide feedback and join the discussion with the development team when you get your hands on the doc.
The playtest doc will be a little shy of 100 pages. Most of the setting info (including our backers' NPCs, towns, and organizations) and won't be published in this free download, but rather in the final doc. The playtest doc will have everything you need to get a feel for the setting, and all the rules: subraces, classes, archetypes, equipment, feats, etc.
Thanks, as always, for backing our passion. And thanks for your patience as we squeeze this thing out there!