Scribd, a site for sharing documents, is coming out of private beta this morning with a fresh Angel investment of $300K on top of their original Y Combinator nest egg of $12,000. Scribd is most easily described as a text version of YouTube. It is a social network that lets you tag, share, and comment on uploaded documents (.doc, .pdf, .txt, .ppt, .xls, .ps, .lit).

Scribd is not just a carbon copy of YouTube. They borrowed a lot of the basic design principles, but also took advantage of the written format by including flexible file formats for download and upload along with some interesting analytics tracking. Documents can be displayed and embedded as html or the under-utilized, and faster-than-a-pdf, Flash paper format. They can be downloaded as .pdf’s, .docs, .txt, and even .mp3 files. The mp3 version is created by Scribd’s text-to-speech package (powered by Nuance) that lets you listen to the text of your document in a quivering British accent (downloadable example here). People have uploaded all sorts of documents for the private beta, like this guide to dating and seduction for dummies, or this less than legal copy of Visual C++ in 21 days. Scribd also lets you “geek out” on all the analytics generated by documents you post, such as how many votes and views your piece gets, as well as geographic location and http referrer that brought the reader there.

We’ve seen a lot of different social networks pop up around different mediums, photos, video, and even audio, but dominating a medium is no guarantee of an easy business model, as the “For Sale” sign on audio-focussed Odeo reminds us. So far social sites around the written word have dealt with books, rather than user generated, or at least user-uploaded content. Scribd lets people do something new, we just need to wait and see how far people go with it.

See our coverage of SlideShare as well.