We are building something that can do everything the current  PlanetMath software can do, and quite a bit more.

Note: these (proposed) features can be put into correspondence with User Stories.

forum

We're building on top of  Vanilla forums, so we get lots of standard forum features for free. done

math support

We've enhanced Vanilla with support for mathematical communication in LaTeX, using  LaTeXML. MathML is fast and is the foundation of several other useful features, and, moreover, done. (We use MathJaX for browsers without MathML alpha, see #284)

encyclopedia

Implemented via our Articles plugin, among other things this recovers PlanetMath's legacy feature in which "every encylopedia article has its own discussion forum attached"; we'll support various source formats, including sTeX (semantically-enriched TeX). alpha, see #175

automatic links

we plan to connect PlanetMath's legacy autolinker into the new system to recover the legacy feature of autogenerated links. However, we aim to provide more control to authors. not yet started, see #20

offline editing

we will store articles in  git and  Subversion repositories which are all kept in sync with the web frontend. in progress, see #35, #149

easy to install

Planetary is easy to install on Ubuntu and similar systems, and we're writing up install instructions for Mac OS X and Fedora. in progress, see #255, #271

rich metadata-based interactions

we plan to create a rich metadata environment around the articles and other site content, which will be useful for everything from permissions management to content personalisation. alpha, see #45, #142, #150

post by email

We want to make it possible to participate in just the discussions you're interested in, from the comfort of your email client. not yet started, see #34

backwards compatibility

We aim to have lossless support for all of the legacy interaction modes from PlanetMath/Noosphere by August, 2011 in progress, see #14, #18

problems and solutions

In addition to hosting Encyclopedia content, Planetary will support problems and solutions, making Planetary sites useful as learning resources hackup, see #152

in-browser services

Users will be able to interact with content on the formula or symbol level hackup, see #164

network-based navigation

We will support navigation by graphs showing theory dependencies in progress, see #148

i18n support

We will support multiple different languages and correspondences between them hackup, see #299

executable papers for next-generation literate programming

Building on several of the features described above, we will be able to deliver support for workflows based on various "Weave" formats, and for documenting main-stream programming projects in a style that provides advantages over standard wiki, tracker, or JavaDoc-like methods not yet started, see #360