Fwiw, I am using Xfbdev exclusively on Corepure64. I have had no issues thus far running any applications except conky, which I replaced with gkrellm2. I am using jwm, leafpad, and firefox-34.0.5 with Xfbdev, and can watch YouTube videos with html5.
I get this working on my hardware (Intel HD3000) using the following boot codes with grub2:
menuentry "6.x-64" {
linux /boot/vmlinuz64 quiet noswap nozswap tce=sda10 home=sda10 opt=sda10 restore=sda10/backup lst=6.x64.lst mydata=6.x64 video=vesafb:ywrap,mtrr:3 pause
initrd /boot/corepure64.gz
set gfxpayload=1366x768x32
}
(I have had to modify the dependency lists for cairo and gtk2 to remove the Xorg/xorg-server dependencies, otherwise they reset the Xserver to Xorg)