If you have been following packages additions you may have noticed the addition of a couple of packages some weeks ago:
While our TeX distributions already ship them (pdftex and mpost), the first two are standalone packages and the last two are eselect modules to easily switch and use them.
With the bump to TeX Live 2008 I’ve made it possible to switch between different versions instead of being bound to what has been shipped with the release. This means that they will get bumped more frequently than they used to.
For the pdftex case, it is currently the same version that comes with TeX Live 2008 with the difference that the standalone version is patched to use poppler instead of its bundled xpdf library. I’ve prefered to leave the xpdf library as default for TeX Live because that is what upstream is using but some people asked for it to use poppler instead and a lot of other distributions (debian, fedora and their derivatives) are using it as the only way. That will probably make it easier to get improvements and security fixes on that side. If you wish to try it, install pdftex and eselect-pdftex and use “eselect pdftex” to set the standalone package as your default pdftex!
As for mplib, it is a reworked and rewritten version of the good old metapost. It can be used as a library (as luatex does) but you can also switch your default mpost interpreter to be it via the eselect-mpost package. Upstream says it is a work in progress but so far I have not seen any problem with it.
By the way, I have unmasked TeX Live 2008 today so that means ~arch users will upgrade to this release and can try these alternatives out of the box.