Binary package hint: xorg
I was attempting to boot the Herd 5 CD with the regular installation option (as opposed to the safe graphics mode one, which I am writing this from).
After the initial load graphic (bar filling up okay, though there was an odd line of orange at the left end of the bar) I get a black screen with a blinking "_" character in the top left corner. This is normal as far as I know.
After this, though, the screen goes completely black and a few minutes are spent with the CD whirring along and evidently something happening in the background. After this it freezes, the CD stopping its spinning, and while the power is still on nothing of consequence seems to be happening.
This is a laptop (Fujitsu Amilo 1437G with ATI Mobility Radeon x700 graphics card) that had to be booted from safe mode in 6.06 LTS as well.
thanks for giving enough information right from the start ;)
this bug has been marked as duplicate of #22985. You could try a daily snapshot of the livecd, and if it works with you that's just fine. If it doesn't, unmark this as a duplicate of that bug.