Knoppix 5.1 and the progress towards Etch release are covered in this weeks news from Distrowatch.
And it is found here
Although the days of twice-per-week KNOPPIX live CD releases seem to be a thing of the past, it doesn't mean that the project has been abandoned. In fact, we might be in for Christmas surprise soon. Klaus Knopper in Knoppix 5.1 Mini-Announcement: “To give you a brief overview about what we have done recently, and what's still pending, here is a short list.”