Yiiiiiha … I love good news.
As published on the official Slackware website Slackware 13.0 will come with an officially supported 64bit version. From the announcement:
[tap tap tap]… Is this thing on?
Ready or not, Slackware has now gone 64-bit with an official x86_64 port being maintained in-sync with the regular x86 -current branch. DVDs will be available for purchase from the Slackware store when Slackware 13.0 is released. Many thanks go out to the Slackware team for their help with this branch and a special thank you to Eric Hameleers who did the real heavy lifting re-compiling everything for this architecture, testing, re-testing, and staying in-sync with -current.
We’ve been developing and testing Slackware64 for quite a while. Most of the team is already using Slackware64 on their personal machines, and things are working well enough that it is time to let the community check our work.
We’d like to thank the unofficial 64 bit projects for taking up the slack for us for so long so that we could take our time getting everything just right. Without those alternatives, we would have been pressured to get things out before they were really ready.
As always — have fun!
Pat and the Slackware crew
I’m looking forward to install it on my machine! 
