As the last update of Slackware-Current showed that there will be a support for GPT (GUID Partition Table) for the next Slackware, perhaps it's good to know what GPT is all about. I believe Rod Smith's tutorial on his website should clearly describe what GPT is all about and how does it solve older MBR scheme limitations.
Eric Hameleers has added gdisk (GPT fdisk) to his repository to support GPT for new installation, but i think it will be included in -Current tree soon enough, as the current fdisk will not be able to detect or use GPT due to it's limitations.
For those who wanted to convert their partition scheme from MBR to GPT, please read this tutorial as there's a big difference on how both schemes works. As always, the man page is one of the best resources available on Open Source environment