We are not that familiar with any recent developments.

However, when we covered the Sugya in Menachos, we were in touch with Saul Kaplan, Ph.D., who says that he has produced a steadfast blue dye from the Janthina (which he catches himself), in his home laboratory in Rechovot. He kindly sent us a Janthina shell to prove to us that its color is blue. You can read about his findings in Levi Kitrossky's article at www.tekhelet.com/kitrossky/tekhelet.htm (seach for "Kaplan" to skip to the relevant section), where he discusses your question concerning the color of the Janthina dye. You can also see Kaplan's own website at www.realtekhelet.com .

I hope this was helpful for you.

Y. Shaw